Fix 2: Check for the Required Access Rights If not, enable the Add-on/Extension by repeating the above steps. If so, delete the faulty Add-on/Extension according to its instruction. Step 4: Check if the Firefox not responding error is fixed. Step 3: In the pop-up window, click on Restart, and then choose Start in Safe Mode. Step 2: Click on Restart with Add-ons Disabled to go on. Step 1: Select the ≡ option from Firefox to open the submenu, and then click Help and choose Troubleshooting Information. Given to that fact, you can try entering Safe Mode to delete the faulty Add-on/Extension.
In most cases, the faulty Add-on/Extension can cause the Firefox not working error.
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