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[object Window]

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  • Last reply by cor-el

dtaenzer
dtaenzer
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I am running the latest FireFox (77.0.1) on Mac OS 10.15.4. Occasionally when I return to a tab that I see

[object Window]

This seems to happen most frequently for Google apps (e.g. gmail) but I have seen it for other pages. I have seen this when all extensions are turned off.

Any ideas on how to fix this?

I am running the latest FireFox (77.0.1) on Mac OS 10.15.4. Occasionally when I return to a tab that I see [object Window] This seems to happen most frequently for Google apps (e.g. gmail) but I have seen it for other pages. I have seen this when all extensions are turned off. Any ideas on how to fix this?

Chosen solution

Do you have any extensions that deal with tabs ?

[object Window] would suggest there there is something wrong with JavaScript.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

You can try to reinstall Firefox and drag the current Firefox installation to the Trash.

You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

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All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

Do you have any extensions that deal with tabs ?

[object Window] would suggest there there is something wrong with JavaScript.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

You can try to reinstall Firefox and drag the current Firefox installation to the Trash.

You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.