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firefox and ublock origin

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When I open Firefox. Firefox Will NOT open any websites. If I disable ublock origin then enable again Firefox works but I get all the ADS. What I have to do is: Close firefox and restart Firefox but then I get this message "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Sometimes I have to restart Firefox as many as 10 times before Firefox works. I got to the point where I stop after the second try and just switch to Brave browser.

Before: Firefox use 99%. Brave Use 1% Now: Firefox use 75%. Brave use 25%

When I open Firefox. Firefox Will NOT open any websites. If I disable ublock origin then enable again Firefox works but I get all the ADS. What I have to do is: Close firefox and restart Firefox but then I get this message "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Sometimes I have to restart Firefox as many as 10 times before Firefox works. I got to the point where I stop after the second try and just switch to Brave browser. Before: Firefox use 99%. Brave Use 1% Now: Firefox use 75%. Brave use 25%

Chosen solution

Note that signing into you sync account can carry over issues no matter how new the Windows or Firefox installation is.

Try changing DNS over HTTPS (DoH) to "Off" or "Max Protection" and in Connection Settings change "Use system proxy settings" to "No proxy".

Avoid any third-party antivirus or security software that may be interfering.

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All Replies (11)

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Hi

Have you made any settings changes to uBlock Origin?

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ublock origin is stock. No changes made. I am on Windows 10 IoT LTSC 2021 Firefox 124 b9 This problem has been going on for about 6-9 Months. Windows has been reinstalled about 3 times. Thanks for any help.

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Does this problem occur with the main Release version of Firefox (version 123)?

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Does it still happen in a new profile? An easy way to test a new profile is to install Developer Edition and see if it happens there or refresh your existing profile. Make sure you stay signed out of your sync account when testing.

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Happens with Stable and Beta. My Firefox account is very new. I reinstall Firefox and all extensions so everything is new.

Every 3 months: New install of windows. New install of Firefox. New install of Extensions. New install of all programs.

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Chosen Solution

Note that signing into you sync account can carry over issues no matter how new the Windows or Firefox installation is.

Try changing DNS over HTTPS (DoH) to "Off" or "Max Protection" and in Connection Settings change "Use system proxy settings" to "No proxy".

Avoid any third-party antivirus or security software that may be interfering.

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Don't enable HTTPS-Only Mode fixed the problem.

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UPDATE: Problem is back. Tried zeroknight suggestion. In Enhanced Tracking Protection I turned off Cookies and Tracking Protection. Did NOT help.

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Reinstall the Visual C++ Redistributable.

Do you have any active enterprise policies listed in about:policies?

Try disabling any third-party modules in about:third-party.

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I uninstalled Firefox, Cleared Mozilla and Firefox entries in registry and Restart Windows. Reinstall Firefox Stable and install extensions one by one. Restart Firefox. Made my changes in about:config one by one. Restart Firefox. This is 6 times in the last 60 days that I reinstalled Firefox. The only change I made was to Disable Automatic Updates. Everything is now working good for now. I will stay on Firefox Stable for now. Thank You to zeroknight for all your help.

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I still have the same problem. Nothing seems to fix it. I will just live with it.