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On my desktop, when I click the Firefox icon, it sends the screen off the top left-hand corner of my computer. It just disappears. How can I open Firefox?

  • 5 replies
  • 1 has this problem
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  • Last reply by neddy

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I rebooted my computer and when I press the Firefox icon a screen disappears into the top left corner of my computer. How can I open Firefox?

I rebooted my computer and when I press the Firefox icon a screen disappears into the top left corner of my computer. How can I open Firefox?

All Replies (5)

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Same problem. Especially annoying when I have several tabs open but have minimized the icon to the taskbar. I can open it by left clicking on the small pop-up from the task bar and selecting maximize. It will then open to the full screen - but that's not how I want it. What's going on?

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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 or Localstore.rdf files.

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 files. Then rename or delete them. Restart Firefox.

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Thanks for your reply. I was hopeful, but when I got to Profiles I did not find either of those files. What I found were files starting as folllows:

3arsfxjm.default

u7yaa9 06opmozs

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Files, or folders? Use the search box to find those files.

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Thanks., Found the xulstore file - it was in a folder called old Firefox data. I've deleted it. The localstore file was not found on my computer.

I hope this solves the problem. Many thanks.