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Weird bar won't go away, causes inconvenience

  • 6 replies
  • 1 has this problem
  • 7 views
  • Last reply by FredMcD

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Since downloading the most recent Firefox, I've noticed this thin bar running along the bottom of my Firefox browser windows, above the add-on bar. It's only a few pixels thick, composed of three lines - white, theme color, white.

It wouldn't be a problem, except if I click and drag it up, it creates this black space between it and the add-on bar, and when I drag it back down to get rid of that space, it also creates and drags down some blank space below the bookmarks toolbar, which displays whatever theme I'm using; any space not covered by the theme picture is solid-colored. And I can only get rid of all this extra space if I create a new window and move all my tabs over.

The first picture is what happens when I accidentally drag it up, then back down; the second shows both the top and bottom blank spaces.

I'd like to get rid of it.

Since downloading the most recent Firefox, I've noticed this thin bar running along the bottom of my Firefox browser windows, above the add-on bar. It's only a few pixels thick, composed of three lines - white, theme color, white. It wouldn't be a problem, except if I click and drag it up, it creates this black space between it and the add-on bar, and when I drag it back down to get rid of that space, it also creates and drags down some blank space below the bookmarks toolbar, which displays whatever theme I'm using; any space not covered by the theme picture is solid-colored. And I can only get rid of all this extra space if I create a new window and move all my tabs over. The first picture is what happens when I accidentally drag it up, then back down; the second shows both the top and bottom blank spaces. I'd like to get rid of it.
Attached screenshots

All Replies (6)

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What you see might just be the separator be=tween the Firefox window and the Windows Task bar.

Did you check that this isn't the Windows Task bar that you are modifying and not something in Firefox?

In that case you should be able to lock this bar to prevent dragging its height via the right-click context menu.

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It's not the taskbar or the edge of the browser window.

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window
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It almost sounds like one of the built in tools, like Inspect Element, was turned on. But not working / displaying properly.

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It's not the inspect element tool. I restarted firefox in safe mode and the bar disappeared, and reappeared when I re-enabled the addons; however it's not longer creating space below the bookmarks toolbar when I pull it up and down, so I'd count this as solved.

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It's possible one of your add-ons is causing the issue. If you want;

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control>(Mac:<Command>)<Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is detective.