This is not a bug of the extension, but rather in VSCode itself: microsoft/vscode/issues/201603
When two extensions have this in package.json
"contributes": {
"configurationDefaults": {
"editor.tokenColorCustomizations": {
and user settings doesn't have "editor.tokenColorCustomizations" saved, then one extension will override the other.
In my case Github Copilot overrides AutoIt-VSCode settings and I don't see any syntax highlighting in the output pane.
For now, we could possibly create a work around by merging that setting into user's config on startup.