3.8.26

3.8.26 (2022.7.15):

• Make some user styles written for old versions of TST effective. See the related issue also for more details.
• Prevent zoom-in/out by pinch-in/out on macOS.
• Add a secret option enableWorkaroundForBug1763420_reloadMaskImage for an ability to deactivate a workaround for the missing icons problem.
• Update ru locale by wvxwxvw. Thanks!

3.8.25

3.8.25 (2022.7.8):

• Restructure options about new tabs behavior to make more understandable.
• Introduce workaround for missing icons problem.
• Add special favicons for blocked pages.
• Update fr locale by tbertels. Thanks!

3.8.24 (2022.6.2):

• Shift twisties in tabs to avoid covered by the scrollbar, on macOS, Linux and Windows 11.
• Keep label of group tabs correctly after they are moved.
• Send tab-mouseover and other notifications to helper addons correctly after the sidebar is reopened.
• Better auto-sizing of the dialog for confirmation on grouping of tabs.
• Deactivate a workaround of problems around wrong coordinates of dragend events on Firefox 99 and 100 (the bug 1767165) on other versions.
• API improvement: Add a new notification message type new-tab-processed to handle new independent tabs.

3.8.23 (2022.5.1):

• Introduce a workaround of problems around wrong coordinates of dragend events on Firefox 99 and later (the bug 1767165). It reduces unexpected detaching of tabs especially on a rightside placed sidebar. This workaround can be disabled by unchecking enableWorkaroundForBug1767165_fixDragEndCoordinates via TST Options - "Development" - "All Configs".

3.8.22 (2022.4.22):

• Now you can search bookmark folder items incrementally by key inputs, on the bookmarks folder chooser UI.
• Better auto-sizing of the dialog for confirmation of closing tabs.
• Match appearance of multiselected tabs in the Proton theme to Firefox 99's one (follow to changes introduced at the bug 1751807).
• Don't open dialogs as modal, on the debug mode.
• API improvement: Add a new notification message type try-collapse-tree-from-other-expansion to block collapsion of tabs from expansion of another tree.

3.8.21 (2022.2.13):

• Accept dragged items from TST Bookmarks Subpanel 1.2.4 and later.

3.8.20 (2022.2.8):

• Fix odd behaviors around drag operations on Firefox 97 and later.
• Inherit container from the active tab to new tabs more safely by reopening, without losing their URL.
• Accept double quotations in tab titles for a bookmark title.
• Don't expand tree by long-press of the Ctrl key, when Ctrl-Tab handling is not granted.
• Show "gear" favicon for "about:config" tabs (follow-up of a change on Firefox 98).
• Update de locale by SammysHP. Thanks!

3.8.19 (2022.1.13):

• Show tabs with readable background color on the combination of "High Contrast" theme and the dark color scheme of Windows 10, on Firefox 96.0 and later.
• Update ru locale by wvxwxvw. Thanks!

3.8.18 (2021.12.26):

• Keep TST's sidebar page loaded in regular tabs even if tabs are dropped on some situations, for example a combination with Tree Style Tab in Separate Window and TST's option to deactivate tab detaching.
• Add a secret option to deactivate sync configs across devices via Firefox Sync (TST's options => Development => All Configs => syncEnabled). This was introduced for a workaround about high CPU usage problem triggered by sync.

3.8.17 (2021.12.15):

• Attach tabs sent from other devices to the tree correctly, even if they are sent while the receiver Firefox is not running and browser.tabs.insertAfterCurrent is true.
• Put a set of tabs from other device together in a place instead of jumped positions if possible, when browser.tabs.insertAfterCurrent is true. (Set a secret option fixupOrderOfTabsFromOtherDevice to false when you want to deactivate the behavior.)
• Respect the right-to-left mark at the beginning of a page title.
• Better appearance of the counter for collapsed descendant tabs in the Sidebar theme.
• Don't collapse tree by double-click on tab closeboxes. It accidentally collapsed the closing tree and closed all descendant tabs unexpectedly.
• Treat middle-click and accel-click actions on the "New Tab" command in the context menu on tabs same to actions on the "New Tab" button, in the sidebar.
• <tab-item-substance>, <tab-label> and <span class="label-content"> now inherit data-tab-id and data-window-id attributes from the parent element (<tab-item>) for more customizability with custom user styles.
• Highlight tabs with "attention" class same as Firefox's native tabs even if they are not faviconized.
• Use highly-visible (darker) background certainly with the "High Contrast" theme on Linux.

3.8.16 (2021.11.11):

• Fade-out long tab labels to left or right, only based on the direction of the label text themselves instead of a global option.
• Remove an option to set global text direction of tab labels.
• Update ko locale by OctopusET. Thanks!

3.8.15 (2021.10.25):

• Apply container information saved by Container Bookmarks correctly for tabs opened from a bookmark folder by the "Open All as Tree" context menu command.
• Collapse tabs dropped onto a collapsed tree correctly, when the drop target parent tab is kept collapsed by TST Lock Tree Collapsed.
• Add a secret option to deactivate API for other addons: APIEnabled
• Update zh_TW locale by SiderealArt. Thanks!

3.8.14 (2021.10.15):

• Apply given colors to the toolbar button icon, menu icons and the sidebar header icon, if the theme provides rich information (ex. Colorways of Firefox 95 and later).

3.8.13 (2021.10.3):

• Fix unexpectedly invisible children when a parent tab is restored and collapsed tabs are re-attached to the restored parent.
• Outdent tab via API correctly when a child tab is outdented to the root level with its descendants.
• Update zh_CN locale by NightSharp. Thanks!

3.8.12 (2021.8.26):

• Update scrollability status of the tab bar even if there are some "hidden via WebExtensions API, but visible by CSS hack" tabs.
• Reduce (deactivate) mis-detection of the sidebar position on some unstable cases: leftside non-primary and high-dpi screen.
• Use an info icon same to the one in the Proton theme of Firefox itself, for network error pages.
• Suppress unexpected expansion after a parent tab lost its focus, while tab swhiching via Ctrl-Tab.
• Open the options page when some drag-and-drop options are chosen in the shorthand menu on the toolbar icon.
• Reload the sidebar automatically for unexpected fatal error while its initialization, to reduce failing of sidebar initialization.
• Update ru locale by wvxwxvw. Thanks!
• Update ko locale by OctopusET. Thanks!
• Update zh_CN locale by NightSharp. Thanks!

3.8.11 (2021.8.17):

• Show a confirmation to apply "Right Side" appearance for the sidebar panel shown at the right side when it is initially detected.

3.8.10 (2021.8.17):

• Show a confirmation to apply "Right Side" appearance for the sidebar panel shown at the right side when it is initially detected.

3.8.9 (2021.8.15):

• Apply appearance matching to sidebar position (left or right) automatically by default. After you switch the siderbar position, you need to reopen TST's sidebar panel to apply matching apperance.
• Introduce an expert option to allow detach dragged tab from the window even if it is dropped near the sidebar, for people using privacy.resistFingerprinting=true.
• Better tree restoration on browser startup, if the delay to detect duplicated tabs is configured for recent versions of Firefox.
• Better compatibility with addons which reopen the initial tab of a new window immediately (e.g. Temporary Containers).
• Import and export all configs more safely with sanitization of device specific config keys.
• API improvement: introduce new notifications tabbar-overflow and tabbar-underflow.
• API improvement: <a href="https://github.com/piroor/treestyletab/wiki/API-for-other-addons#messages-no...

3.8.4

3.8.4 (2021.6.20):

• Update overflow state of tabs more correctly to avoid unexpected covering of the bottom most tab with the new tab button.
• Update visibility of tab context menu items correctly even if it the initial run.
• Restore tree structure more correctly for tabs reopened via Shift-Ctrl-T after closing of multiple tabs at a time.
• Allow to override size of pinned tabs area (--pinned-tabs-area-size), subpanel area (--subpanel-area-size), and new tab button area (--after-tabs-area-size) easily by overriding these variables with custom user style.
• Rescue errors of options UI initialization, and reveal options UI even if some options don't work.
• Don't close the new tab button long-press menu on mouseup. (regression on 3.8.2)
• Restore lost compatibility with user styles containing --multiselected-color. (regression on 3.8.2)

3.8.3 (2021.6.13):

• Recontstruct "Proton" theme for better compatibility with Firefox's themes, dark mode of the platform, and GTK theme.
• Avoid needless 1sec delay of confirmation dialogs.
• Update ru locale by wvxwxvw. Thanks!

3.8.2 (2021.6.11):

• More natural appearance of the theme "Proton" matching to Firefox's Proton theme.
• The new tab button is now draggable as a link to the URI about:newtab, with the Shift key. This means that you can open a new tab at arbitrary position in the sidebar via drag and drop.
• Add icons to the new tab action selector panel for better user experience.
• Accessible labels of faviconized tabs from screen readers and voice recognition systems.
• Allow to open about:newtab links dropped in the sidebar.
• Show confirmation dialogs in the sidebar more safely even if they are triggered by quick actions.
• Never open new tab by middle click on confirmation dialogs shown in the sidebar.
• Never show invalid "undefined" item in the list of other devices.
• Apply the height of the user style editor immediately when a different value is imported.
• Open new blank tab as a child correctly, even if the insertion position is configured as "no control" or "next to the recently opened".
• Re-introduce an option to change the color of the toolbar icon, for better accessibility.
• Don't clear drop position marker while dragging, on Linux environment.
• Save changed config of the new tab insertion position via the right click menu on the toolbar button correctly.
• Try applying the background color to the sidebar ASAP.
• Allow to toggle muted state of tabs even if it is not sound-playing (if the mute button is shown forced by custom user styles).
• Subpanel contents now have its owner window's ID as the windowId URL parameter, by NiklasGollenstede. Thanks!
• Subpanel is now restricted to a page contained in the provider extension itself, by NiklasGollenstede. Thanks!
• API improvement: Add ability to handle and override events on the new tab button via notification messages with types new-tab-button-mousedown, new-tab-button-mouseup and new-tab-button-clicked.
• API improvement: Add ability to control extra contents in the new tab button via messages with types set-extra-new-tab-button-contents and clear-extra-new-tab-button-contents.
• API behavior change: tab-clicked type message is now delivered only when both tab-mousedown and tab-mouseup are not canceled.
• Update de locale by SammysHP. Thanks!
• Update ko locale by BoredSomeone. Thanks!

3.8.1 (2021.5.7):

• Prevent inifinite toggling of the sidebar scrollbar on macOS, when there are enough number of tabs which triggers overflowing. The fix was unexpectedly lost on the released version 3.8.0.
• Update ru locale by wvxwxvw. Thanks!

3.8.0 (2021.5.5):

• Restructure behaviors about closing and moving of a parent tab.
  • In the sidebar, now there are some permanently fixed behaviors and some configurable presets:
    • Closing a parent tab with collapsed tree: closes the entire tree.
    • Moving a parent tab with collapsed tree: moves the entire tree.
    • Moving a parent tab with expanded tree: behaves according to configurations under the section "Drag and Drop".
  • There is a preset for people using Firefox's native tab bar as an UI to operate solo tab. In this case all tab operations done outside of the sidebar (Firefox's native tab bar, keyboard shortcuts, or other addons) are treated as operations for solo tabs, not tree of tabs.
  • There is a preset for people desireing TST to control tabs as trees always. In this case all tab operations are treated same as operations in the sidebar, even if it is done on Firefox's native tab bar, keyboard shortcuts, or other addons.
  • Otherwise you can configure behaviors for each case: closing of a parent with expanded tree in the sidebar, closing of a parent with collapsed/expanded tree outside of the sidebar, moving of a parent with collapsed/expanded tree outside of the sidebar, and more options for cases with closed sidebar.
• Better accessibility information for the sidebar. This change should help controlling of the sidebar via speech recognition.
• Add the simulated "New Tab" context menu command on tabs.
• "Close Tabs to the Bottom" and "Close Other Tabs" context menu commands now skips collapsed descendants of the context tab.
• Open tabs from a bookmark folder with correct order. (This looks to be a regression on recent versions.)
• Prevent inifinite toggling of the sidebar scrollbar on macOS, when there are enough number of tabs which triggers overflowing.
• On macOS, in-tab padding is correctly applied avoiding the scrollbar covers clickable UIs. (It was applied to wrong side.)
• Proton theme: Show container identifier line at top of pinned tabs.
• Proton theme: Remove separator border between pinned tabs and regular tabs.
• Apply the icon color or the text color defined by the active theme to TST's toolbar button icon, context menu icon, and the sidebar panel switcher.
• Rebuild sidebar contents more certainly when mis-synchronization between the main process and the sidebar contents is detected.
• Becomes to more robust around tabs reopened immediately by other addons like Temporary Containers.
• Becomes to more robust around closing/moving of parent tabs as solo tabs.
• Don't show needless "Send Tab to Device" simulated context menu item in the context menu on non-tab area.
• Open duplicated tabs based on the configuration more correctly.
• Expose an expert option UI to control the number of scroll lines for keyboard shortcuts.
• The height of the subpanel is now saved and restored for each provider addon.
• Better appearance for the subpanel switcher: more easily recognized as a switcher UI.
• Accept icon images with non 16px size for the subpanel switcher.
• API improvement: now you can specify initialHeight or fixedHeight for your subpanel.
• API improvement: custom state of tabs are added/removed safely even if they are given as any type value not a string.
• API improvement: Support CSS length delta and position parameters for the scroll API.
• API improvement: Support duration parameter for the scroll API.
• API improvement: Add new API stop-scroll to cancel in-progress scroll animations.
• Update ru locale by wvxwxvw. Thanks!

3.7.4

3.7.4 (2021.3.31):

• Add a theme like Proton experimentally. Proton is the next UI theme of Firefox itself.
• Rename the theme "Plain" to "Photon". Photon is the current UI theme of Firefox itself.
• Restructure tab context menu items to match to the one on Nightly 89.0a1.
• Add a new expert option to close a parent tab as a solo tab by triggers outside of TST, even if it has collapsed children, with visible sidebar.
• Increase the maximum size of the user styles about 12KB.
• Add a debug option to configure the delay to detect duplicated tabs.
• API improvement: introduce create which creates a new tab bypassing TST's tab position control behaviors.
• Update ru locale by wvxwxvw. Thanks!

3.7.3 (2021.3.1):

• Add support for Firefox 88+ compatible "Close Tabs to the Left (Top)" context menu command.
• Prevent the cached helper addon IDs to be synchronized via Firefox Sync. This should solve problems around initialization of helper addons after TST is updated dynamically.
• Don't apply "Tabs from any other trigger" option for new tabs opened from TST's new tab button and the new tab action menu.
• Show tab drag feedback images at bottom-right of the cursor like Firefox does, for better visibility of drop targets.
• Update ru locale by wvxwxvw. Thanks!

3.7.2 (2021.2.19):

• Limit maximum rows of pinned tabs (50% height of the sidebar by default) and allow to scroll pinned tab rows with the wheel.
• Keep tree structure more robustly for tabs immediately closed and reopened with different contaienr by any other addon.
• Don't restore closed tabs doubledly on a restoration with Ctrl-Shift-T.
• Restore root level tabs to their original position correctly, even if "new tabs from any other trigger" option is changed. (regression on recent versions)
• Clean up only dummy group tabs even if "Close descendants too" is chosen for options under the "When a parent tab is closed or moved just as a solo tab" => "Custom" section.
• Apply "When a parent tab is closed or moved just as a solo tab" => "Recommended behavior for people who still use the native tab bar of Firefox itself also" => "Replace closed parent with a dummy tab and keep the tree" behavior correctly. (regression on recent versions)
• Show confirmation for closing descendants when a collapsed tree is closed via keyboard shortcuts. (regression on recent versions)
• Move detached descendants after all other existing descendants automatically, to keep correct tree structure. (regression on recent versions)
• Add an expert option to change acceptable accelerator key to match the one on Firefox itself modified via ui.key.accelKey.

3.7.1 (2021.2.12):

• Consistent the position of the new tab action selector button in both regular and private windows.
• Update ru locale by wvxwxvw. Thanks!

3.7.0 (2021.2.9):

• Show in-tab container indicators (colored bars) with a styling more similar to Firefox's native one.
• Introduce syntax highlighing in the user styles editor (based on the CodeMirror.)
• Remember the height of the user styles editor.
• Cancel the visual gap of tabs produced with dynamically showing/hiding toolbars only when it is triggered by mouse operations on the sidebar in regular windows (not fullscreen mode), by default.
• Add a new expert option to control how tabs to be opened for any other cases not covered by existing options.
• Deactivate "Reopen in Container" and other container tab related features for private windows, like as Firefox itself does.
• API improvement: introduce *-of-<id> suffixed keywords to get tabs based on relations from any arbitrary tab.
• API improvement: introduce lastDescendant keyword to get tabs based on tree structures.
• Update ru locale by wvxwxvw. Thanks!
• Update de locale by SammysHP. Thanks!

3.6.5

3.6.5 (2021.1.8):

• Show favicons same to Firefox's built-in for about:logins, about:profiling, about:protections and about:robots tabs.
• Detect tabs opened from external applications correctly. (The detection result was wrong: only new tabs opened with openerTabId while all Firefox windows were inactive were detected as "opened by external applications".)
• Don't show not-initialized-yet menu elements while the startup process.
• Update ru locale by wvxwxvw. Thanks!

3.6.4 (2020.12.21):

• Prevent to mis-shift the sidebar content with regular tabs, non-fullscreen windows placed at coordinates like (*, 0).
• Expose an expert option to deactivate shifting of the sidebar contents with temporarily shown toolbars.
• Fix incompatibility with Tree Style Tab Mouse Wheel on Firefox 84 and later. (Thanks to @MISONLN41!)
• Ensure moved active tab visible even if it is moved via keyboard shortcuts Ctrl-Shift-PageUp/PageDown.
• Turn moved active tab visible even if it is moved from an collapsed tree to the top level via keyboard shortcuts.
• Hide the dummy tab behind the background carten completely.
• Provide custom properties for theme colors with different opacity, with a numeric suffix like -10 per 10%. For example --theme-colors-tab_background_text-30 means "the color ame to tab_background_text but 30% opacity".
• Update ru locale by wvxwxvw. Thanks!

3.6.3 (2020.12.2):

• Cancel the visual gap of the sidebar contents when visibility of Firefox's toolbar is toggled for some special cases: about the bookmarks toolbar for new tabs on Firefox 84 and later, and about the navigation toolbar in the fullscreen mode. You can access invisible tabs top of the sidebar with hovering on the top edge of the sidebar contents.
• Context menu commands "Close Other Tabs" and "Close Tabs to Bottom" now don't close hidden tabs like Firefox's native commands.
• Better compatibility with other addons around tabs moved across windows by other players like Simple Tab Groups. TST now don't clear openerTabId of such tabs.
• Better response for F1 key or the toolbar button to toggle the sidebar on Firefox 73 and later.
• Reduce the timeout to kill zombie connections for an already closed sidebar, from 5 seconds to 0.5 seconds.
• Restore tree strucutre correctly for a tab which was a parent and reopened via Ctrl-Shift-T.
• Network error pages now have the warning favicon rendered with visible color, like Firefox's native tabs.
• No drag session is started anymore for tabs when Do nothing / Do nothing is chosen for the drag action.
• Prevent starting of accidental drag sessions for clicked tabs from Firefox's bugs around IPC more aggressively.
• Create bookmarks to the bookmarks toolbar by default like Firefox 84 and later.
• Guide to click the button in a desktop notification with the phrase "click the button" instead of "click here", on Linux environment.
• Avoid losing the cusror position of the input field for the user styles while typing, more certainly.
• Scroll the sidebar to newly opened tabs even if animation effects are disabled. (regression on 3.5.33)
• Indicate new tabs opened outside of the visible area with blue flash even if animation effects are disabled. (regression on 3.5.33)

3.6.2 (2020.11.19):

• Stable toggling of the sidebar via F1 key or the toolbar button. (The action was sometimes broken unexpectedly due to zombie connections between closed sidebar pages and the background page.)
• Never lose the cusror position of the input field for the user styles while typing.
• Suppress unexpected detaching or moving of tabs from unexpectedly dispatched dragend, more aggressively.
• Add new choice to disable drag-and-drop of tabs completely, for experts.
• Fix API error: { type: 'get-tree', windowId: (integer) } now returns an array of root tree items (instead of just single tree item), as described at the API document.

3.6.1 (2020.11.10):

• Fix broken custom confirmation dialogs. (regression on 3.6.0)
• Update ru locale by wvxwxvw. Thanks!

3.6.0 (2020.11.06):

• Implement the "Send Tab to Device" context menu command based on Firefox Sync. It is just a workaround implementation based on the Sync Storage, because a genuine WebExtensios API to use Firefox Sync won't be implemented for now.
• Remove "Group Tabs", "Ungroup Tabs", "Indent" and "Outdent" menu commands and keyboard shortcuts. Now they are separated to a helper addon TST More Tree Commands.
• Better compatibility with addons providing features to move tabs across windows, e.g. Simple Tab Groups. Now TST keeps tree structure of moved tabs more safely.
• Update overflow status of the tab bar after tabs are moved across windows.
• On macOS, show custom dialogs in a temporary tab instead of a window if the browser window is in the fullscreen mode. (Because to avoid custom dialogs to be oepend as new fullscreen windows.)
• Support "toolbar" color for container icons.
• Support "fence" icon of Facebook Container addon for container icons, by maciekmm. Thanks!
• Add debug options to activate platform specific behaviors.
• Update ru locale by wvxwxvw. Thanks!
• Rename intenral directory name of the Korean locale from kr to ko, by dfkdream. thanks!

3.5.34

3.5.34 (2020.10.22):

• Create group for tabs opened from a pinned tab correctly, even if "no control" is chosen for the insertion position of new child tabs. (regression on 3.5.33)

3.5.33 (2020.10.20):

• Add an explicit choice to open new child tabs at the position next to the recently opened child or the opener parent tab, like Firefox does with the preference browser.tabs.insertRelatedAfterCurrent=true.
• Add an expert option to insert new child tabs at the top or the end, when they are dropped onto a parent.
• Add some expert options to configure checkbox status of group tabs created for each context.
• Simulate Firefox's focus control behavior like the combination browser.tabs.insertRelatedAfterCurrent=true and browser.tabs.selectOwnerOnClose=true more correctly. (On old versions the parent tab was unexpectedly became the successor of a closed child tab even after manual focus changes.)
• More stabilize behaviors around auto-grouping of tabs opened from a pinned tab.
• Don't reload tab inifinitely when a URL is loaded on a group tab (it was originally reported as the bug 1671500.)
• Update ru locale by wvxwxvw. Thanks!

3.5.32 (2020.10.11):

• Save "Warn me when I attempt to close multiple tabs" checkbox state correctly for the confirmation dialog about closing multiple tabs via the closebox.
• Handle tabs which are immediately opened and closed more safely. It will improve compatibility with other tab addons which reopen new tabs, e.g. Temporary Containers.
• Handle closing of multiple tabs more safely for already closed tabs.
• Scroll the tab bar to expanded tree. (regression on recent versions)
• Scroll the tab bar to expanded tree even if animations are disabled.
• Restore closed tree with their original order and tree structure more correctly.
• Keep and restore checkbox state of group tabs correctly. (regression on recent versions)
• Fill the user styles field with imported configs immediately.
• Accept ext+treestyletabi:sidebar as an alias of ext+treestyletab:tabbar.

3.5.31 (2020.10.4):

• Restore group tab title correctly. (regression on 3.5.30)

3.5.30 (2020.10.4):

• Add ability to specify arbitrary title for the sidebar page with the parameter title, like ext+treestyletab:tabbar?title=.... This is for better compatibiliy with helper addons using TST's sidebar page e.g. Tree Style Tab in Separate Window.
• Load sidebar page with the chosen builtin theme immediately when it is loaded via ext+treestyletab:tabbar URL. This is for better compatibiliy with helper addons using TST's sidebar page e.g. Tree Style Tab in Separate Window.
• Apply browser theme and user styles to the sidebar page more safely when the builtin theme information is not specified via the URL parameter. Thank you Lej77!

3.5.29 (2020.10.4):

• The "Load from File" button for the user styles now allows you to choose images and embed them as data: URIs.
• The user styles input field now accepts drag and drop of files (but this new behavior is available only when the options page is opened in a separate tab instead of embedded in the addons manager, due to the bug 1408756).
• Reopen new tab from external application with specific containers correctly.
• Never reopen a new tab with a container inherited from the current tab or the parent tab, when the tab is opened with non-default container.
• Never show needless vertical scrollbar in group tabs even if there are too many tree items.
• Never draw tree of tabs multiple times in a group tab. (regression on recent versions)
• Support two digits year with the placeholder $SHORT_YEAR% for names of generated bookmark folders.
• Update ru locale by wvxwxvw. Thanks!

3.5.28 (2020.9.29):

• Better visibility of active tabs and closeboxes on the high contrast mode.
• Fix regressions on 3.5.24 around auto-correcting of tabs order after multiple opened tabs.
• Fix wrong successor tab control around child tabs and their closed opener parent tabs: the next sibling of a closed child active tab will become active instead of the parent tab.
• Initialize restored group tabs more certainly.
• Search text dropped onto the sidebar with the default search engine correctly.
• Add regular choices for drag and drop options to prevent detaching of dropped tabs to a separate window.
• Add ability to control container of new tabs from three options: no inheritance, inherit from the current tab, or inherit from the tree parent.
• Show throbber with the color same to tab labels on a dark theme.
• Remove needless underline of tab labels on the "Sidebar" theme.
• Set "Plain" as the default theme on Windows and Linux correctly.
• Fix wrong behaviors of "All Configs" UI: apply imported configs to options UI immediately and treat decimal values as valid for some numeric options.
• Update ru locale by wvxwxvw. Thanks!

3.5.27 (2020.9.6):

• Reduce more visual motions when they are reduced by platform configs.
• Add an expert option to activate animation effects regardless platform configs.
• Update de locale by SammysHP. Thanks!

3.5.26 (2020.9.3):

• Deactivate animation effects globally when they are reduced by platform configs.
• Deactivate throbber animation when animation effects are reduced by platform configs.

3.5.25 (2020.9.2):

• Optimize performance around the "lock scroll position" behavior.
• Add "Ungroup Tabs" context menu command.
• Open the changelog from the update notification popup.
• Update ru locale by wvxwxvw. Thanks!
• Fix typo in Enghlish locale by reaverxai. Thanks!

3.5.24 (2020.8.28):

• Simulate "lock scroll position of the tab bar while middle tabs are closed via mouse operations" behavior of Firefox's native tab bar.
• Shrink the width of the confirmation dialog for closing tabs with very long titles.
• Detect a tab is opened from a bookmark more certainly, even if its hostname starts with "www."

3.5.23 (2020.8.26):

• Drop support for some built-in themes: "Vertigo" and "Mixed". They can be alternated with user styles.
• Simulate appearance of close boxes in Firefox's native tabs more, for hover and active state.
• Close the tab by click on the close box, even if the cursor has moved out from the close box and went back while the button is pressed, like close boxes in Firefox's native tabs.
• Set default color of icons for the "No Decoration" theme.
• Save cached tree state as a metadata related to each window instead of individual tab.
• Attach tabs opened from dropped links to existing tree based on their position. (regression on recent versions)
• Update ru locale by wvxwxvw. Thanks!

3.5.22 (2020.8.12):

• Shift-click to multiselect tabs between the clicked tab and the active tab correctly, even if it happens after focus move from outside of TST.
• Restore closed tabs with their correct old position even if their visibility was switched by something other addons like Simple Tab Groups.
• Save very large user style rules more safely.

3.5.21 (2020.8.8):

• Apply user style rules to group tabs again. (regression on 3.5.20)
• Update ru locale by wvxwxvw. Thanks!

3.5.20 (2020.8.7):

• Use the SVG icon insetad of the PNG icon on all situations.
• Apply system colors by default only on Linux with non-dark platform theme.
• Extend the maximum size of the user style rules from 8KB to 48KB.
• Notify new features with a desktop notification instead of an annoying tab.

3.5.19 (2020.8.4):

• Use the toolbar color defined in the theme as the background color of each tab surfaces.
• Accept themes with colors defined in various formats hsl(), hsla(), and their variations.

3.5.18 (2020.8.4):

• Safely restore tree for reopened tab even if its old parent was already closed. (regression on 3.5.16)
• Safely restore tree for reopened tab on the "Fix up tree structure with visible tabs automatically" mode. (reg...

3.5.13

3.5.13 (2020.7.21):

• List tabs to be closed/grouped in the confirmation dialog to represent which tabs are going to be operated.
• Update tabs' activated, pinned/unpinned, hidden/shown, and collapsed/expanded states correctly. (regression on 3.5.12)
• Highlight multiselected tabs on "Metal" and "Sidebar" theme correctly. (regression on 3.5.12)
• Restore tree structure for "Undo Close Tabs" operation more correctly.

3.5.12 (2020.7.12):

• Stabilize handling of asynchronously notified messages from the background page to the sidebar page. As the result, wrong indentation and collapsed/expanded state should disappear especially around session restoration.
• CSS selectors for container tabs like tab-item[data-contextual-identity-name="Personal"] is now available for user styles.

3.5.11 (2020.7.12):

• Show confirmation for multiple tabs closing after a tab is completely closed from outside of TST instead of showing before the tab disappears, for better response on tab closing.
• Ignore click on the blank area if it is performed immediately after a click on a tab and at the same coordinates.
• Add ability to import/export user styles.

3.5.10 (2020.7.11):

• Show fonts with normal weight on Windows 7 Classic theme.
• Define default keyboard shortcuts statically with the manifest.json. It should reduce unexpected disappearing of default shortcuts. You can unbind default shortcuts on Firefox 74 and later, but it is impossible on older versions.
• Don't produce any scrolling for popup menus (on the new tab button and others) if the focused item is already visible in the view area.
• Update ru locale by wvxwxvw. Thanks!

3.5.9 (2020.7.10):

• Constantly promote tab by drag and drop after its present parent tab. (regression on recent versions)

3.5.8 (2020.7.10):

• Fix incompatibility with TST Hoverswitch and other addons using tab-mouseover API by Klemens Schölhorn, thanks!
• Reduce needless confirmation about closing of multiple tabs triggered by actions from outside of TST.
• Fix unexpected missing centering of the startup tab.
• Update ru locale by wvxwxvw. Thanks!

3.5.7 (2020.7.6)

• Process redirection of shorthand URI (ext+treestyletab:) with query parameters correctly.

3.5.6 (2020.7.5)

• Group "Close Tabs to the Bottom" and "Close Other Tabs" context menu items under a submenu "Close Multiple Tabs", like Firefox 78 does.
• Add ability to restore the recently closed set of tabs, triggerred with a restoration of tabs in the set.
• Activate/deactivate the animation effect for updating of indentation with the animation option.
• Deactivate all animations automatically when animation effects are disabled by the platform itself.
• Add ability to configure middle click on the new tab button same as Ctrl-click.
• Quicken detection and grouping of new tabs opened from a bookmark folder.
• Show the container name in the tooltip on container tabs, like Firefox does.
• Better container support in group tabs.
• Add ability to change column width in group tabs. Now custom style definition like :root.group-tab { --column-width: 30em; } does it.
• Cancel TST's default action for click on tabs more correctly, via API notifications tab-mousedown and tab-mouseup.
• Add ability to open the sidebar in separate window with the URI ext+treestyletab:tabbar?windowId=(Window.id). This change should help addons like the TST in Separate Window.
• The count of opened tabbar pages are now notified to helper addons via the sidebar-show and sidebar-hide notification APIs.
• Better responses for tab switching on Firefox 79 and later, with the new API browser.tabs.warmup().
• Reduce the total amount of sync storage a little, and cleanup of needless sync data. It is limited until 100KB, and please remind that you cannot put data larger than 16KB for each option especially custom style rules.
• Update ru locale by wvxwxvw. Thanks!

3.5.5 (2020.6.6):

• Fix broken appearance of the sidebar after window move across multiple screens with different DPI.
• Group new tabs automatically by default only when they are detected as tabs opened from bookmarks in one folder. As the result the configuration UI for auto-grouping feature is now very simplified.
• Shrink clickable area of checkboxes and radio buttons in the options page.
• Simuate Ctrl-click and Shift-click actions on the new tab button in Firefox's native tab bar. Now Ctrl-click opens a new next sibling tab with inherited container, and Shift-click opens a new window.
• Expand tree if a new tab is added into a collapsed tree as a next of a parent tab with browser.tabs.insertAfterCurrent=true.
• Unify the simulation option for browser.tabs.closeTabByDblclick=true to the option for the double-click action on a tab.
• Apply extra user styles to contents of group tabs also.
• Update ru locale by wvxwxvw. Thanks!

3.5.4 (2020.5.5):

• Show semi-modal dialogs more smartly. The annoying flash from a small window before the dialog is finally shown goes away.
• Add an option to show dialogs in the sidebar, under the "Appearance" section of the options page. It takes back the old behavior around dialogs for confirmation and bookmarking.
• Reduce needless space below rendered columns of tabs tree in group tab pages.
• Better compatibility with recent versions of Firefox Multi-Account Containers.
• Better compatibility with Container Bookmarks: now TST respects container information stored to bookmarks when TST opens bookmarks as a tree.
• Support drag-and-drop between TST's tabs and subpanels. This improvement includes a new API get-drag-data.
• Support native context menu on subpanels. This improvement includes a new API override-context.
• Unprefix fake-contextMenu- API to contextMenu-*. But fake- prefixed verisons are still available for backward compatibilitty.
• Update de locale by SammysHP. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.5.3 (2020.4.28):

• Handle dismissed semi-modal dialogs correctly.
• Optimize semi-modal dialogs a little.
• Optimize bookmark folder chooser UI for very large number of bookmarks.
• Set the "Other Bookmarks" folder as the default choice of the bookmark folder chooser UI if the configured default folder was removed.
• Update ru locale by wvxwxvw. Thanks!

3.5.1 (2020.4.24):

• Show popup windows correctly on Firefox ESR68. (regression on 3.5.0)

3.5.0 (2020.4.23):

• Show dialogs as semi-modal popup windows.
• Hide the context menu item "Reopen in Container" in private windows. This behavior is compatible to Firefox's one.
• Update ru locale by wvxwxvw. Thanks!

3.4.10

3.4.10 (2020.4.19):

• Open bookmarks as tabs with their correct title, via the "Open All as a Tree" context menu command on a bookmark folder.
• Open bookmarks more correctly via the "Open All as a Tree", even if browser.tabs.insertAfterCurrent is true.
• Introduce a new notification type API: try-fixup-tree-on-tab-moved.

3.4.9 (2020.4.16):

• Put bookmarks undar a new folder with their tree structure information automatically, when they are created from tabs via drag and drop.
• Allow to move down a tree with the keyboard shortcut Ctrl-Shift-PageDown correctly.
• Don't leave invisible orphans after only their parent tab is moved via drag and drop or other operations.
• Show the fake context menu correctly even after any helper addon is unloaded.
• Return root tabs for an API call like {type:"get-tree",windowId} correctly.
• Notify try-redirect-focus-from-collaped-tab and try-expand-tree-from-focused-collapsed-tab with correct focusDirection for the first time or cases with a circulation.
• Make tabs visible automatically when tabs are attached/detached via APIs.
• Performance improvement around APIs by account-login. Thanks!
• Fix typo in English locale by jaens. Thanks!
• Update zh_CN locale by no1xsyzy: add an access key for the menu item "Tree of tabs". Thanks!

3.4.8 (2020.3.27):

• Fix ghost "active, highlighted" state of newly opened tabs which lost its focus imediately.
• Fix accidental unregistration of helper addons from unhandled errors.
• Fix invalid tab property of tab-mouseup and tab-clicked notifications on mouseup after moving from non-tab element.
• Suppress error ater the first regular (unpinned) tab restoration.
• Better description for drag and drop behavior options.
• Update zh_CN locale by NightSharp. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.4.7 (2020.3.17):

• Fix undroppability of links and some objects to tabs. (regression on recent versions)
• Add a link to open the options page itself in a new tab, at the top of the page.
• Add "Reset All" button to the bottom of the options page.
• Update de locale by SammysHP. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.4.6 (2020.3.12):

• Add "Collapse this Tree Recursively" and "Expand this Tree Recursively" commands for the context menu and keyboard shortcuts.
• Support inverted actions of some context menu commands with middle click: reload tree / reload descendants, close tree / close descendants, collapse tree one level / recursively, and expand tree one level / recursively.
• Support multiselected tabs by some context menu commands: reload tree, reload descendants, close tree, close descendants, close others except the tree, collapse tree, and expand tree.
• Add "Collapse this Tree Recursively" and "Expand this Tree Recursively" commands for the context menu and keyboard shortcuts.
• Add an expert option to control the behavior when the current tab is closed with collapsed descendants and hidden sidebar.
• Change the default behavior around closing tab without sidebar to "for people who use the native tab bar". It was unexpectedly overwritten by the auto migration mechanism.
• Add a new option recursively to collapse-tree and expand-tree APIs.
• Add a new paremter button to parameters notified to fake-contextMenu-click listeners.
• Update ru locale by wvxwxvw. Thanks!

3.4.5 (2020.3.9):

• Better compatibility to Firefox's native tabs around behavior and user experience about Ctrl-Click and Shift-Click on UI elements in tabs (twisties, sound playing buttons, and closeboxes). Now these actions just changes multizelection state of tabs.
• Better compatibility with the combination of TST Lock Tree Collapsed and TST Active Tab in Collapsed Tree.
• Add a new API notification message type: try-redirect-focus-from-collaped-tab.

3.4.4 (2020.3.8):

• TST's tab is activated on a mousedown event. This behavior was unexpectedly lost at TST 3.1.0. (regression)
• Skip collapsed tree while tab switching via Ctrl-Tab/Ctrl-Shift-Tab, including cases they are lcoked as collapsed by some other helper addons.
• tab-mouseup and tab-clicked are notified even if tab-mousedown is canceled. I totally confused the spec about mouse events with key and input events. This fixes incompatibility regression with a helper addon Move unloaded tabs for Tree Style Tab.

3.4.3 (2020.3.7):

• Better compatibility with known custom user styles.

3.4.2 (2020.3.7):

• Fix confused color scheme with the "Plain Dark" theme on Linux. (regression on 3.4.0)

3.4.1 (2020.3.6):

• Fix unclaickable sound playing indicator problem. (regression on 3.4.0)

3.4.0 (2020.3.6):

• Remove "Lock as Collapsed" feature. Now it is available as a helper addon: TST Lock Tree Collapsed
• Remove "Tab Drag Handle" feature. Now it is available as a helper addon: TST Tab Drag Handle
• Remove keyboard shortcut customization UI from the options page, because Firefox ESR68 has it.
• Show in-content confirmations correctly (regression on lately versions of Firefox.)
• Toggle muted state of descendants of collapsed tree more certainly.
• Don't show throbber animation in a blank group tab if tree rendering is disabled.
• More safe for bookmarks with URLs impossible to be opened by an addon.
• More safe for non-tab drag data. (regression on recent versions)
• Add checkbox to grant a permission required to show in-content confirmation.
• Rename an option autoExpandOnCollapsedChildActive to unfocusableCollapsedTab and make effective on cases tabs going to be collapsed by collapsing parent tree.
• Better support for a special favicon about about:devtools-toolbox tabs.
• Add new API message types: set-extra-tab-contents, clear-extra-tab-contents and clear-all-extra-tab-contents.
• Add new API notification message types: tab-dblclicked, tree-collapsed-state-changed, try-move-focus-from-collapsing-tree, try-expand-tree-from-focused-parent, try-expand-tree-from-focused-bundled-parent, try-expand-tree-from-attached-child, try-expand-tree-from-focused-collapsed-tab, try-expand-tree-from-long-press-ctrl-key and try-expand-tree-from-end-tab-switch.
• Notifications and operations tab-mouseup, tab-clicked and tab-dblclicked following to tab-mousedown are now canceled by any leading notifications.
• Don't deliver messages around incognito windows to other addons, if they are not allowed to access incognito windows.
• Update ru locale by wvxwxvw. Thanks!

3.3.6

3.3.6 (2020.2.21):

• "Bookmark this Tree" context menu command now bookmarks all multiselected tabs and thier descendants.
• Open dummy group tab with loaded state always, when it is opened by "Open All as a Tree" context menu command on bookmark folders.
• Apply "Mute Tab" and "Unmute Tab" context menu commands to the tree recursively when the target tab has collapsed descendants. If you run these commands on an expanded tree, only target tabs are processed.
• Apply muted/unmuted state to the tree recursively by clicking of the sound playing button only on a collapsed tree. If you click buttons on expanded tabs, only clicked tabs are affected.
• Fix edge case problem of auto-tree-repair when tabs are switched to shown from hidden.
• Fix edge case problem of tree attaching with hidden tabs.
• Suppress needless reloading after some tabs are removed immediately after other tabs are moved.

3.3.5 (2020.1.24):

• Don't skip peinding (unloaded) tabs on Ctrl-Shift-Tab.
• Skip collapsed tabs on Ctrl-Tab/Ctrl-Shift-Tab focus rotation more correctly, just after the active tab was closed.
• Pinned tab is now droppable before the first unpinned tab.
• Unnpinned tab is now droppable after the last pinned tab.
• Detect drop position on a tab as top or bottom for pinned but not-faviconized tabs.
• Add an expert option to control the behavior: collapse other trees when a collapsed tree is auto-expanded by a long-dragover.
• Update ru locale by wvxwxvw. Thanks!

3.3.4 (2020.1.14):

• Fix unexpected error from cyclic references.
• Reduce accidental modifications of the tree structure after tabs are shown/hidden.
• Skip collapsed tabs on Ctrl-Tab/Ctrl-Shift-Tab focus rotation more correctly, just after the active tab was closed.
• Add kr locale by BoredSomeone. Thanks!

3.3.3 (2020.1.12):

• Support Firefox versions after the bug 1565170 is fixed.
• Fix confused tab focus after some tabs are hidden and shown.
• Don't expand locked-collapsed tree with a long press of the Ctrl key while Ctrl-Tab/Ctrl-Shift-Tab tab switching is in progress.
• Allow to expand locked-collapsed tree when a descendant tab gets focus directly.
• Hide options and other tab contents until they are initialized.

3.3.2 (2020.1.9):

• Ignore double click on any clickable UI in tabs except the closebox, to prevent accidental close or other reactions.

3.3.1 (2020.1.9):

• Add ability to toggle locked-collapsed state of a tree by double click.
• Don't expand locked-collapsed tree when a new child tab is attached.
• Update counter of collapsed descendants correctly on tabs restored from the cache. (regression on recent versions)
• Update ru locale by wvxwxvw. Thanks!

3.3.0 (2020.1.8):

• Introduce the "Lock as Collapsed" feature. When the state is locked via the context menu command or a keyboard shortcut, TST keeps the tree collapsed when it or its any descendant get focused.
• Show "Open All as a Tree" in the bookmarks context menu only when the context menu is opened on a folder.
• Add an option to avoid pending (discarded) tabs to be activated accidentally when the active tab is closed or an ancestor tree of the active tab is collapsed.
• Introduce a new option to activate/deactivate the confirmation for closing multiple tabs with a normal click on a closebox of a parent tab with its collapsed subtree.
• Change twisty's appearance to Photon-style one.
• The delay to ignore too short drag action produced by the bug 1561879 on macOS become configurable.
• Brush up options UI and hide expert options by default. And now more detailed options are exposed in the expert mode.
• Add new API message types: toggle-tree-collapsed, lock-tree-collapsed, unlock-tree-collapsed and toggle-lock-tree-collapsed.
• Add more special tab aliases for some API messages: nextVisible, previousVisible (prevVisible), and versions with the suffix Cyclic.
• Add support for a special window ID active for an API message type scroll.
• Reduce needless dependency to an outdated library webextensions-lib-tab-id-fixer, by adroitwhiz. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.2.6

3.2.6 (2019.12.27):

• Apply dark color scheme to the sidebar only when the "Apply Browser Theme" option is active.
• Give higher priority to the color scheme defined by the theme.
• Don't break tree when multiple tabs are opened in the middle of an existing tree at just same time.
• Add a new context menu command "Open All as a Tree including subfolders" for bookmark folders to open them recursively.
• Don't open needless tabs for non-bookmark items by the "Open All as a Tree" command.
• Open tabs from the "Open All as a Tree" command as discarded by default.
• Update descendant tabs counter correctly when a child tab is detached from a window.
• Add bundledTabId property to the tab item returned/notified via the API.
• Add new proxied properties deltaX and deltaZ to notified scrolled messages via the API.
• Unlocalize the name of this addon in Japanese, for better findability. As the result the parent context menu item for extra commands is renamed to "Tree of tabs".
• Don't finish title editing of a group tab by hitting the Enter key to finish a text composition.
• Don't refresh the subpanel when a helper addon is registered with no subpanel.
• Fill the list of subpanels correctly after the sidebar is reloaded.
• Pinned tab is now marked as "unread" only when their title is really changed in the background.
• Update ru locale by wvxwxvw. Thanks!
• Update zh_CN locale by Siyuan Xu. Thanks!

3.2.5 (2019.11.14):

• Show drop marker with visible color even when a dark color scheme is applied.
• Show the scrollbar in the sidebar with dark color when a dark color scheme is applied on some themes: Plain, (Plain Dark,) Vertigo and Mixed.
• Don't show accesskeys for command names on the keyboard shortcut manager of Firefox itself.
• Re-calculate some colors dyanmically when the system color scheme is changed.
• Return a tab object of the opened group tab for an API call of the group-tab command correctly.
• Update de locale by SammysHP. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.2.4 (2019.11.7):

• Apply dark color scheme for options in about:addons, when the default color sheme of the platform is dark.
• Rearrange and relabel options for general New Tab actions and special actions for more understandability.
• Show attention color correctly on Vertigo and Mixed with the Dark color scheme. (regression on 3.2.3)
• Show default favicons in group tabs with the text color. (regression on 3.2.3)
• Apply system colors and Firefox theme correctly even if the default color scheme of the platform is dark on Linux. (regression on 3.2.3)
• Add a new API command open-all-bookmarks-with-structure to open bookmarks in the specified folder with tree structure.

3.2.3 (2019.11.5):

• Apply dark color scheme on Plain, Vertigo and Mixed, when the default color sheme of the platform is dark.
• Apply dark color scheme for options in tab, group tab, and startup tab, when the default color sheme of the platform is dark.
• Update color scheme of Plain, Plain Dark, Vertigo and Mixed as more friendly for Photon Design System and Firefox's default color scheme.
• Apply last selected subpanel and its height after restart even if the session restoration is disabled.
• Show highlighter of hovered background tabs with Plain type themes correctly. (regression on 3.0.x)
• Update zh-TW locale by Bo-Sian Li. Thanks!
• Update ru locale by wvxwxvw. Thanks!

3.2.2 (2019.11.3):

• Show notification when multiple tabs are closed by one action without any confirmation. It allows you to cancel the operation by clicking it.
• Duplicate tabs as a sibling of the source tab correctly even if the source tab was active.
• Highlight active tabs correctly on some edge cases.
• Allow to detach dragged tabs more ceratainly from the window when tabs are dropped outside the sidebar. This is based on a workaround for the bug 1548949, and as a trade-off this change introduced a new intentonal regression on a edge case: tabs are duplicated when tabs are dropped to another Firefox instance (tabs imported to the receiver Firefox and tabs are also detached to a new window on the source Firefox).
• Update overflow state of tab labels and tooltips more correctly. (regression on 3.2.0)
• Fix backward compatibility for old custom user styles. (regression on 3.2.0)
• Allow to close tabs after a tab close was canceled on a beforeunload event. (regression on recent versions)
• Update ru locale by wvxwxvw. Thanks!

3.2.1 (2019.10.29):

• Apply the option to control inheritance of the container from the current tab to a tab opened from outside Firefox.

3.2.0 (2019.10.28):

• Separate an option to control new tabs from outside Firefox.
• Open search result tabs opened from about:addons tab as children.
• Save tree structure to bookmarks when multiple bookmarks are created from a tree, via commands provided by TST itself.
• Add a new context menu command "Open All as a Tree" for bookmarks.
• Migrate bookmarked internal URLs (like moz-extension://...) to shorthand URLs (like ext+treestyletab:...) automatically, for better mobility.
• Restore collapsed state of tabs correctly even if they are placed under an expanded tree and the parent is placed under a collapsed tree.
• Reduce FPS of throbber animations from 60 to 30. (See also the bug 1511095.)
• Show group-tab items with folder icon, in the contents area of a group tab.
• Re-implement the view with custom elements (Web Components) for better maintainability. (Thanks to saneyuki!)
• Update ru locale by wvxwxvw. Thanks!