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When I start up Firefox on Mac 10.11.6, using Firefox 74.0, I get a message that says "File not found."

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  • Last reply by cor-el

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On startup I get a message that says "File not found. Could not find file at jar:file:///Applications/Firefox.app/Contents/Resources/browser/omni.ja!/chrome/en-US/locale/branding/browserconfig.properties." I have never done anything with this file. When I switch tabs, it goes away. I have tried safe mode, but that doesn't solve it.

On startup I get a message that says "File not found. Could not find file at jar:file:///Applications/Firefox.app/Contents/Resources/browser/omni.ja!/chrome/en-US/locale/branding/browserconfig.properties." I have never done anything with this file. When I switch tabs, it goes away. I have tried safe mode, but that doesn't solve it.

Chosen solution

The browserconfig.properties file was used in older Firefox versions to set a localized homepage. This has been changed in Firefox 63 to have support for non-localized homepages, so seeing a reference to this file is likely a leftover from an older Firefox version.

You can check "browser.startup.homepage: pref on the about:config page.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

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This problem usually means that a Firefox file is lost or damaged. It can often be corrected simply by performing a Clean Reinstall. That would replace any damaged or missing files.

Hope this helps.

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Seçilmiş Həll

The browserconfig.properties file was used in older Firefox versions to set a localized homepage. This has been changed in Firefox 63 to have support for non-localized homepages, so seeing a reference to this file is likely a leftover from an older Firefox version.

You can check "browser.startup.homepage: pref on the about:config page.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.