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I use Nightly. My system is 64bit. The tabs can not close. Please check it.

  • 3 replies
  • 1 has this problem
  • 92 views
  • Last reply by cor-el

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At the options, the session remember is active.

After opening program some tabs are open automatically. Then I open new tabs but can not close them.

At the options, the session remember is active. After opening program some tabs are open automatically. Then I open new tabs but can not close them.

Chosen solution

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.

You can check for problems with preferences.

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

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Chosen Solution

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.

You can check for problems with preferences.

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

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I disabled the "Tab Mix Plus" then no problem. Unfortunately the source of the problem is Tab Mix Plus add-on. Thank you @cor-el.

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You can try to ask advice at the Tab Mix Plus forum.