Load Web Pages in Firefox Sidebar: How-To

Updated 5 November 2026 · Standard formula, shown below

Yes, you can load web pages in Firefox’s sidebar. This article explains exactly how to do it, what the sidebar is for, and how to get the most out of it.

What Is the Firefox Sidebar?

The Firefox sidebar is a vertical panel that appears on the left (or right, if you drag it) side of the browser window. By default, it shows your bookmarks, history, or synced tabs. You can open it with the keyboard shortcut Ctrl+B (bookmarks) or Ctrl+H (history) on Windows/Linux, or Cmd+B/Cmd+H on macOS. The sidebar is designed to let you browse your saved items or history without leaving the current page. However, it is not a general-purpose web browserâ€”it is a panel for browser features.

Can You Display a Website in the Sidebar?

Out of the box, Firefox does not have a built-in option to load an arbitrary website in the sidebar. The sidebar is not a web page viewer; it is a container for browser panels like bookmarks, history, and extensions. If you want to see a website in a side panel, you need an extension. There are several add-ons that do this, such as “Side View” (Mozilla’s own experiment) or “Web Sidebar”. These extensions add a button that opens a small web view in the sidebar, letting you keep a reference page open while you work in the main window.

How to Load a Web Page in the Sidebar (Using an Extension)

Here is the general process, which works for most sidebar extensions:

Go to the Firefox Add-ons page (addons.mozilla.org) and search for “sidebar” or “side view”.
Choose an extension that suits you. Read its description and reviews to make sure it is maintained.
Click “Add to Firefox” and confirm the installation.
Once installed, you will see an icon in the toolbar (or a menu item). Click it to open the sidebar.
In the sidebar, you can type a URL or use the extension’s controls to load a specific page.

Some extensions let you set a default page (like a news site or a chat app) that loads every time you open the sidebar. Others let you send the current tab to the sidebar with a right-click menu.

Why Would You Want a Web Page in the Sidebar?

There are several practical reasons:

Reference material: Keep a documentation page, a dictionary, or a translation service open while you write or code in the main window.
Social media or chat: Monitor a messaging web app without switching tabs.
Music or video: Play a streaming service in the sidebar while you browse other sites.
Productivity: Have a to-do list or calendar web app always visible.

The sidebar is narrower than a normal tab, so it is best for sites that are readable in a small column. Most modern websites will adapt, but some may not look great.

Common Problems and Solutions

If you try to load a page in the sidebar and it does not work, here are the usual culprits:

The site refuses to load in an iframe: Many sites (like Google, Facebook, or some banking sites) send an HTTP header called X-Frame-Options that prevents them from being displayed in a frame. The sidebar often uses an iframe, so these sites will not load. You cannot force them to load; it is a security feature.
The extension is outdated: Firefox updates frequently, and some extensions break. Check for updates or try a different extension.
The sidebar is too narrow: Some sites need a minimum width. You can drag the sidebar edge to make it wider, but it is still limited.
Cookies or login issues: The sidebar may use a separate browsing context, so you might not be logged in. Some extensions let you use the same cookies as the main window; others do not.

How to Choose the Right Extension

Not all sidebar extensions are equal. Consider these factors:

Privacy: Check what permissions the extension asks for. A sidebar extension should only need access to the current tab and the ability to create a sidebar panel. Avoid extensions that ask for “access to all websites” unless they need it to function.
Features: Some extensions allow multiple sidebar panels, custom widths, or the ability to open links in the sidebar. Decide which features you need.
Maintenance: Look at the last update date. An extension that has not been updated in years may not work with the latest Firefox.
Open source: If you are privacy-conscious, prefer extensions that are open source and have a clear code repository.

Alternatives to the Sidebar

If you cannot get a page to load in the sidebar, here are other ways to keep a page visible:

Split-screen view: Firefox does not have a built-in split-screen, but you can use the operating system’s window snapping to place two Firefox windows side by side. This gives each page a full browser engine, so all sites work.
Picture-in-Picture for videos: For video, Firefox has a built-in Picture-in-Picture mode that floats a video player on top of any page.
Use a second monitor: If you have a multi-monitor setup, just put the reference page on the second screen.
Bookmarklets or user scripts: For advanced users, you can create a bookmarklet that opens a specific page in a small popup window, though this is not the same as a sidebar.

Frequently Asked Questions

Can I load any website in the Firefox sidebar?
No. You can only load sites that allow being displayed in a frame. Many major sites (like Google, Facebook, and most banking sites) block this for security reasons. You will see a blank or error message instead.

Is there a built-in way to do this without an extension?
No. Firefox’s built-in sidebar only shows bookmarks, history, and synced tabs. To display a web page, you must install an extension.

Will the sidebar slow down my browser?
It can, because the sidebar is essentially another web page running at the same time. If you have a low-memory computer, keeping a heavy site in the sidebar may cause lag. It is best to use lightweight sites in the sidebar.

How do I remove a sidebar extension?
Go to the Firefox menu (three horizontal lines) > Add-ons and themes. Find the extension in the list and click the three-dot menu next to it, then choose “Remove”. The sidebar will disappear.

Can I use the sidebar on Firefox for Android or iOS?
No. The sidebar feature is only available on the desktop version of Firefox. Mobile browsers do not have a sidebar panel.

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