hello PavelkoT.

try restarting firefox in safe mode because no addons will be used. then you can push ctrl+shift+a and addons will come up! :)

this way you can isolate it and let the developers know what it is, just make notes.

It could be the work of one of your add-ons, or it could be Hardware Acceleration. How to disable Hardware Acceleration {web link}

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control> (Mac=<Command>) <Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All Of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is, detective.

The Internal UUID displayed after moz-extension:// is particular to your Firefox. To match it up with the source, you can type or paste about:debugging into the address bar and press Enter/Return to load it. Then you can use Find (Ctrl+f/Command+f) to search for 0cc2b and figure out which one generates that page.

Note that all UUIDs are stored in this pref in JSON format:

• extensions.webextensions.uuids

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.

• http://kb.mozillazine.org/about:config

cor-el said

Note that all UUIDs are stored in this pref in JSON format:

• extensions.webextensions.uuids

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.

• http://kb.mozillazine.org/about:config

I tried and didn't find this UUID in about:config. For me just is strange that some addon affected on about:support.

Solved. Reason was VideoDownloadHelper 7.2.1

Regarding the crashes:

If you are getting the Mozilla Crash Reporter form, your Firefox may have logged some data that would help track down the cause of the problem. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "Firefox crashes - asking for support" for steps to get those crash report IDs from the about:crashes page, and then post some of the recent ones here.