If you don't like the new look of the browser, we will show you how to disable Proton in Firefox 91. Earlier, you could disable it with a couple of settings in about:config. Now, you should use a different method.
Actual versions of Firefox include a new user interface, known as Proton. It is notable for rounder corners, less contrast colors, and other similar changes that make the browser go well with the style of the newest Windows 11. Also, the changes made it more touch friendly.
However, many users didn't welcome the updates to the browser's look. The poor contrast of controls makes it harder to spot elements. Tabs look like buttons and feel completely disconnected from the tab row. There are no separation lines clearly defining tabs which makes multiple tabs look like one connected button. Finally, the huge control spacing looks weird on regular desktop PCs. Also, menus without icons and feel lost and empty.
How to Disable Proton UI in Firefox 91
To disable Proton after updating to Firefox 91, you need to do the following.
- Enable support for userChrome.css
- Apply CSS styles to disable Proton tabs and buttons.
Here are details on each and every step.
Enable support for userChrome.css
By default, Firefox doesn't process userChrome.css or userContent.css files which store user-made customizations for the user interface of the browser. You need to enable them We have a dedicated tutorial on this topic here on Winaero. Here are the steps you need to perform.
- Open Firefox and type
about:configin the address bar. Press Enter.
- Confirm that you accept the risk.
toolkit.legacyUserProfileCustomizations.stylesheetsinto the search box.
- Set the
- Restart the Firefox browser.
Done. This will enable support for CSS customizations in Firefox 91. You can now disable Proton. Here is how.
Disable Proton in Firefox 91 user interface
There is a project on GitHub that maintains the custom style to revert Proton in Firefox and restore its previous look.
To disable Proton in Firefox 91, do the following.
- Click on this link to download the ZIP archive with CSS styles.
- After that, type
about:supportin the Firefox address bar.
- Click on the Open Directory button next to the Profile Directory entry. This will open your Firefox profile folder in File Explorer.
- Extract the Firefox-UI-Fix-photon-style folder from the ZIP archive you have downloaded to that folder.
- Rename the
your firefox profile dir\Firefox-UI-Fix-photon-stylefolder to
- Now, open the chrome folder, and cut (Ctrl + X) the
- Go one level up, i.e. to your Firefox profile dir, and paste the user.js file (Ctrl + V).
- Return to the Firefox
about:supportpage and click on the Clear startup cache... button at the top.
- This will restart the browser. Enjoy the now-classic "Photon" look of Firefox 60x.
That's how you disable Proton in Firefox 91.
Don't turn off other parameters in about:config
While Firefox 91 retains all the *proton* options in about:config. But you should not disable any of them. Please keep them to their default values. Otherwise the customizations you made won't work properly.
They are required to "restyle" the browser's appearance and disable the Proton UI.
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