Updates for upcoming 11.6.0 release

[metastable-void]

Version 11.6.0

New features

• Drag and drop tabs inside a container to reorder them.
• Tab drag and drop between containers.
• New option to disable sorting of tabs.
• Group of containers (supergroups).
• Tags to organize tabs inside a single container.

Improvements and fixes

• Adopted state of art tab sorting algorithm.
• New paths for add-on pages.
• Moved common codes into external libraries.
• Preparation work for a more responsible and performant non-persistent background page.
• Removed legacy codes.
• Translation updates.
• Dependencies updates.
• Bug fixes.