TST Indent Line provides indent lines like Visual Studio Code's one.(This was a built-in feature on TST 2.6.0-3.3.6, and now separated.) TST Tab Drag Handle provides a small tooltip on tab labels to start dragging of tabs for specific operations.(This was a built-in feature on TST 3.3.0-3.3.6, and now separated.) TST Lock Tree Collapsed allows you to lock arbitrary trees as collapsed.TST Auto Group Tabs provides ability to group newly opened tabs automatically in various conditions.TST Active Tab on Scroll Bar shows a marker to indicate the position of the active tab, on the scrollbar.TST Active Tab in Collapsed Tree shows a small tab on a collapsed tree as an alias for the last active tab under the tree.TST More Tree Commands provides more context menu and keyboard shortcut commands to manipulate TST's tree.TST Bookmarks Subpanel allows you to show a small 'Bookmarks' sidebar panel below tabs in the TST's sidebar.It also allows you to close mutiple tabs with long-press on the closebox on tabs. Multiple Tab Handler allows you to select multiple tabs with long-press on tabs.Some extend the behavior of TST's sidebar panel: TST provides an API for other extensions. If it's unnecessary, you can remove it from the toolbar. 'Tree Style Tab' toolbar button also toggles the sidebar.Moreover, each tree will reflect a group of tabs on a similar topic.You'll easily dig and dig deeply, without losing your browsing trail - if you want to go back to the original search result, you just have to switch to the 'root' tab.New tabs opened from these 'child' tabs will appear as descendants of their originating tabs.

For example, if you see a list of search results for a topic, each search result link will open in new child tab.

Such a tree of tabs will behave like a visual browsing history for you.

If you want, you can restructure the tree via drag and drop. Such 'branches' are easily folded (collapsed) by clicking on the arrow shown in the 'parent' tab, so you no longer need to suffer from too many visible tabs. New tabs opened from the current tab are automatically organized as 'children' of the current tab. This extension provides the ability to work with tabs as 'trees'.

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