Sidebery5.6.1

Sidebery is a free and open source sidebar extension for Firefox, which mainly uses tree tabs, panels and groups to organize a large number of web pages. When you open multiple projects, profile pages, or different accounts, it can move content originally squeezed into the top tab bar into a searchable and collapsible sidebar.

It not only arranges tabs vertically, but also integrates bookmarks, history, containers, automatic allocation rules and window snapshots. Sidebery is suitable for users who keep a lot of tabs for a long time, need to split the workspace by tasks, or want to fine-tune the Firefox browsing process.

Core functions

• Tree tab page: Arrange related pages according to parent-child relationship, fold branches, limit levels, and manually color different domain names or tags.
• Panels and Groups: Use multiple tab page panels, bookmark panels, and group pages to split work, learning, and temporary tasks to reduce the mixing of different contexts.
• Container rules: You can bind Firefox containers to panels, and automatically move new labels to designated areas according to URL rules, making it easy to isolate multiple accounts.
• Bookmarks and History: Browse, search, and organize bookmarks and history in the sidebar, and switch between tabs and bookmarks.
• Snapshot and recovery: Save the status of windows and tabs on a schedule, and restore from snapshots when you accidentally close the window or reorganize the workspace.
• Highly customizable: Right-click menu, mouse operations, shortcut keys, drag-and-drop behavior, title display and CSS styles can all be adjusted.

Product Features

The advantage of Sidebery is that it puts the tab tree, workspace, container and snapshot into the same sidebar, and the setting granularity is finer than the vertical tab page that comes with Firefox. It provides a Simplified Chinese interface, and the default data is saved locally; only when synchronization is actively enabled, the data will be sent to the synchronization service selected by the user.

Rich functions also mean more settings. It may conflict with extensions such as Tree Style Tab that move or sort tabs, and it is officially recommended not to enable similar managers at the same time. Firefox also does not allow extensions to directly hide the native top tab bar. If you want to completely hide it, you can only configure userChrome.css. This step is not suitable for users who are new to Firefox customization.

Installation and usage tutorial

1. Confirm that the desktop version of Firefox has been updated to version 140 or higher, then open the Sidebery page from the Firefox add-on store and add the extension.
2. After installation, open the Firefox sidebar and select Sidebery in the sidebar extension list. When using it for the first time, keep the default layout and confirm that tab switching and new creation behave normally.
3. Click the Settings button at the top of Sidebery to create tab panels for work, study, etc. in the “Panel”; when you need to layer them, you can drag tabs to create a parent-child structure or create a new group.
4. Users who use Firefox multi-account containers can bind the container in the panel or container settings, and then add automatic allocation rules by URL. Features involving proxies, clearing cookies, or modifying User-Agent require additional permissions that do not need to be granted when not in use.
5. Enable automatic snapshots in the Snapshot settings and set the retention quantity. After completing the layout, manually create a snapshot to confirm that the recovery entry and save range are as expected.
6. If new tabs appear to be in abnormal positions, moved repeatedly, or initialized chaotically, first disable other tab sorting extensions, and then restart Firefox inspection.

Applicable scenarios

• Data-intensive research: Organize search results, documents, and pages to be read into tree-like branches by topic, and collapse them as a whole when necessary.
• Multi-project office: Create an independent panel for each project to reduce the interference between chat, code, documents and background pages.
• Multiple account isolation: Combine Firefox containers and URL rules to allow different accounts on the same website to enter the designated panel.
• Keep a lot of tabs open for long periods of time: Use auto-uninstall, search, and snapshots to manage infrequently accessed pages and preserve recovery paths.

Free scope and license

Sidebery is free to download from the Firefox Add-ons Store. The source code is released under the MIT license, has no ads, and does not require a subscription. Core tab management, bookmarks, history, containers and snapshots are all free. Optional synchronization relies on third-party services selected by the user, and the related accounts, storage space or service fees are not provided by Sidebery.

Usage evaluation

Sidebery is suitable for people who use Firefox as a long-term workbench: the more tabs, the more obvious the sense of order brought by the tree structure, panels and automatic rules. The official store lists it as a recommended extension. It currently has about 52,000 daily users and a score of about 4.7, indicating that it already has a relatively mature user base.

It is not a lightweight tool that requires no setup at all. You should start with two or three panels for your first configuration, and then enable container rules, custom menus, and CSS once you get used to the tree tabs. The extension requires necessary permissions such as reading and managing tabs. Permissions such as bookmarks, history, proxies, and all website data are related to specific optional functions. It is recommended to enable them as needed.

Update instructions

The current stable version is 5.6.1, released on July 16, 2026. The Firefox official store installation package is about 576.06 KB and requires Firefox 140 or higher. This maintenance update fixes the initialization failure in versions before Firefox 149; 5.6.0 and 5.6.1 were released on the same day. Users using older versions or with abnormal sidebar status at startup should update first.