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On new laptop the userchrome.css I've been using for years doesn't put the tabs on the bottom anymore.

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This exact same userchrome.css still works fine on my pc,both computers are running the same,latest version of Firefox [69]. It also worked fine in my old laptop...like,two days ago before I sold it. I think everything else in the userchrome.css seems to still work on this laptop...spacing,tab height,search box,address bar clear instead of cloudy etc etc...but not the tabs on bottom part.

First pic [capture 1] is the pc with tabs on bottom,how I want them..second pic is this laptop...tabs on top. Any ideas to restore the tabs to the bottom would be greatly appreciated,thanks.

This exact same userchrome.css still works fine on my pc,both computers are running the same,latest version of Firefox [69]. It also worked fine in my old laptop...like,two days ago before I sold it. I think everything else in the userchrome.css seems to still work on this laptop...spacing,tab height,search box,address bar clear instead of cloudy etc etc...but not the tabs on bottom part. First pic [capture 1] is the pc with tabs on bottom,how I want them..second pic is this laptop...tabs on top. Any ideas to restore the tabs to the bottom would be greatly appreciated,thanks.
Attached screenshots

Chosen solution

Hello Haruna, There was a change in Firefox 69.0:

"Firefox no longer loads userChrome.css or userContent.css by default improving start-up performance. Users who wish to customize Firefox by using these files can set the toolkit.legacyUserProfileCustomizations.stylesheets preference to true to restore this ability."

From - See what’s new in Firefox! https://www.mozilla.org/en-US/firefox/69.0/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_campaign=whatsnew

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All Replies (7)

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Chosen Solution

Hello Haruna, There was a change in Firefox 69.0:

"Firefox no longer loads userChrome.css or userContent.css by default improving start-up performance. Users who wish to customize Firefox by using these files can set the toolkit.legacyUserProfileCustomizations.stylesheets preference to true to restore this ability."

From - See what’s new in Firefox! https://www.mozilla.org/en-US/firefox/69.0/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_campaign=whatsnew

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Can you post the content of userChrome.css?

Are the ant @-moz-document url() lines in the userChrome.css file?

You may have to make this change:

@-moz-document url(chrome://browser/content/browser.xul) =>
@-moz-document url(chrome://browser/content/browser.xhtml)
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Hi,thanks very much My_Cheese_Is_Slippin',setting that legacy toolkit thing to true fixed it,the tabs are back on the bottom now...excellent! For some reason that was set to true automatically on my pc,but not on the laptop. Thanks a lot.

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My_Cheese_Is_Slippin' said

Hello Haruna, There was a change in Firefox 69.0: "Firefox no longer loads userChrome.css or userContent.css by default improving start-up performance. Users who wish to customize Firefox by using these files can set the toolkit.legacyUserProfileCustomizations.stylesheets preference to true to restore this ability." From - See what’s new in Firefox! https://www.mozilla.org/en-US/firefox/69.0/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_campaign=whatsnew

Having this problem after an update, just last night, and the toggle is already set. Went to bed with the CSS working, woke up with it broken.

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Where is this file located? toolkit.legacyUserProfileCustomizations.stylesheets

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toolkit.legacyUserProfileCustomizations.stylesheets is not a file, but one of the many preferences that are listed on the about:config page. You can use the search bar at the top of this page to locate this pref and toggle the pref via a double-click on the line or via the Edit button.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

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damien.williams7 said

My_Cheese_Is_Slippin' said
Hello Haruna, There was a change in Firefox 69.0: "Firefox no longer loads userChrome.css or userContent.css by default improving start-up performance. Users who wish to customize Firefox by using these files can set the toolkit.legacyUserProfileCustomizations.stylesheets preference to true to restore this ability." From - See what’s new in Firefox! https://www.mozilla.org/en-US/firefox/69.0/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_campaign=whatsnew

Having this problem after an update, just last night, and the toggle is already set. Went to bed with the CSS working, woke up with it broken.

Found a solution, here, though it comes with the caveat that it apparently won't work on firefox 72

https://www.reddit.com/r/FirefoxCSS/comments/e5o5uq/found_a_fix_for_userchromecss_to_get_the_tabs/