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Not able to switch about:config Tabs.OnTop true/false

  • 5 replies
  • 6 have this problem
  • 2 views
  • Last reply by Moses

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Since the last update for FireFox, on both Mac and Windows, I'm not able to put the Tab's back on the bottom, like I want/used to.

Normally I'll open a tab, and type in About:Config That will open the config page for FireFox, than in the search bar, I'll look for Tabs.OnTop, normally this would be True. And I used to switch this to False, which would have switched the Tab's to the bottom.

But since the update, this does not longer work.

Please help!

Since the last update for FireFox, on both Mac and Windows, I'm not able to put the Tab's back on the bottom, like I want/used to. Normally I'll open a tab, and type in About:Config That will open the config page for FireFox, than in the search bar, I'll look for Tabs.OnTop, normally this would be True. And I used to switch this to False, which would have switched the Tab's to the bottom. But since the update, this does not longer work. Please help!

All Replies (5)

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You have tried restore default Firefox homepage? https://support.mozilla.org/en-US/kb/How%20to%20set%20the%20home%20page

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I did that, just now, after you advised. But now the option "Tabs.OnTop" does not show in the config menu...?

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the tabs.onTop preference is about:config doesn't work any longer in Firefox 29.

You can use either of the following add-ons.

If you don't want to install an add-on, put the following style in the userChrome.css file and restart Firefox. You can use the Stylish add-on instead, if you have it installed.


@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);
/* The above line should appear only once in the file */

#TabsToolbar { -moz-box-ordinal-group: 99 !important }

Also see


One of the developers recently posted this explanation

MikeDeboer said

Each setting you see in a computer program you use requires work; when a developer wants to build something new or improve something, he or she has to go through each related (hidden) setting and test if it still works like before and do that on each platform Firefox runs on. That's Apple's Mac OSX, various flavours of Linux and various flavours of Windows, including Windows XP. This costs time, lots of it, and that amount grows exponentially with each setting that's added. This comes on top of our work to continuously fix, improve and innovate Firefox. 

That's why we also removed the tabs.onTop preference. Awesome community members, who were unhappy about that change, created the Classic Theme Restorer add-on. They deserve our collective hugs.
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Thanks Moses!

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