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private browsing add ons

  • 3 replies
  • 1 has this problem
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  • Last reply by BradS

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Hi. I am trying to figure out why my add ons do not work at all in private browsing. my tab manager fails to save tabs in private mode and adblock does not work at all. what would be the cause of this behavior? I have the option enabled for both to use in private but they refuse to run. thanks

Hi. I am trying to figure out why my add ons do not work at all in private browsing. my tab manager fails to save tabs in private mode and adblock does not work at all. what would be the cause of this behavior? I have the option enabled for both to use in private but they refuse to run. thanks

All Replies (3)

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Hi BradS, when you install an extension, it is only enabled for regular windows by default. Firefox displays a little confirmation panel on the right side of the toolbar with a checkbox to enable it in private windows. If you don't do it then, you still should be able to do it now. Here's how.

Open the Add-ons page -- either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then on the right side, find an extension that needs to run in private windows, and click it to view its Details panel. Scroll down (if needed) to the line with

Run in Private Windows   O Allow  O Don't Allow

And update your preference.

Repeat with other extensions as needed.

Was that it?

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Of course, I missed that last sentence. Try toggling between Don't allow and Allow.

I'm not aware of any global settings that could block all extensions from running in private windows.

The other thing that comes to mind is possibly the extensions.json file has become corrupted in some manner. In that case, you could remove the file and let Firefox rebuild it. This may flush your accumulated extension settings and data so consider it a last resort.

Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" Help > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in File Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > Exit
  • (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then rename extensions.json to something like extensionsOLD.json.

Start Firefox back up again and it should rediscover the installed extensions. Most likely you'll need to enable each one for private.

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Hi. thanks for the suggestions. Still having the same problems.