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forefox acting strange! browser size and position fluctuates

  • 4 replies
  • 1 has this problem
  • 55 views
  • Last reply by FredMcD

steve388
steve388
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I've been using firefox as my default browser since it started, but yesterday it started getting weird. I open the browser and rather than open to the size of my monitor it opened to 1/4 size, next time I opened the browser it opened normally, next time 1/4 size and so on. I've looked at settings and it looks ok (not that I've changed anything recently) When it opens 1/4 size I click the top right to open full size and the 1/4 size browser moves from te left side to the right, the I click the top right full screen and it opens full screen with tools. Really weird! Has there been a screwy update?

I've been using firefox as my default browser since it started, but yesterday it started getting weird. I open the browser and rather than open to the size of my monitor it opened to 1/4 size, next time I opened the browser it opened normally, next time 1/4 size and so on. I've looked at settings and it looks ok (not that I've changed anything recently) When it opens 1/4 size I click the top right to open full size and the 1/4 size browser moves from te left side to the right, the I click the top right full screen and it opens full screen with tools. Really weird! Has there been a screwy update?

Chosen solution

Start Firefox using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh).


Do this several times in a row (open/close/open/close). Is the problem still there?

Read this answer in context 👍 0

All Replies (4)

FredMcD
FredMcD
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https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved You may have corrupt xulstore.json file.

Close Firefox. Open your file browser to this hidden location:

  • Mac: *~/Library/Application Support/Firefox/Profiles
  • Linux: *~/.mozilla/firefox/Profiles
  • Windows: %AppData%\Mozilla\Firefox\Profiles
  • *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles
  • Windows XP: C:\Documents and Settings\<user>\Application Data \Mozilla\Firefox\Profiles\

Search for the above file. Then rename or delete it. Restart Firefox.

FredMcD
FredMcD
more options

Chosen Solution

Start Firefox using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh).


Do this several times in a row (open/close/open/close). Is the problem still there?

steve388
steve388 Question owner
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Thanks Fred, but neither suggestions fixed the issue. Deleting Windows: %AppData%\Mozilla\Firefox\Profiles stopped firefox opening, so I opened the recycle bin and restored the files.

I tried the safe mode as suggested, but that didn't fix it. In the end I "refreshed" Firefox and that did the trick. I think I did click the troubleshoot mode to get to it? Thanks for the Help Fred, you steered me in the right direction.

FredMcD
FredMcD
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steve388 said
Deleting Windows: %AppData%\Mozilla\Firefox\Profiles stopped firefox opening

My instructions were to delete the xulstore.json file. Not the folder.


In the end I "refreshed" Firefox and that did the trick.

That was very good work. Well Done. Please flag your last post as Solved Problem as this can help others with similar problems. Go to that post and click the 'Solved' button to its right.