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Firefox is slow and responds incorrectly to keypresses

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  • Last reply by Scribe

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Since the last update I have refreshed Firefox about 4 or five times. As I use it, it gets slower and slower until it stops responding. On top of this, it is now responding incorrectly to the delete and backspace keys. I often type into forms online and now, if i make an error and press the backspace or delete keys Firefox exits the editing window without saving my work.

I am seriously considering moving to another browser (though not a Microsoft one). Please can you suggest something to help? I am on Windows 10 Pro Insider build 17074.

Since the last update I have refreshed Firefox about 4 or five times. As I use it, it gets slower and slower until it stops responding. On top of this, it is now responding incorrectly to the delete and backspace keys. I often type into forms online and now, if i make an error and press the backspace or delete keys Firefox exits the editing window without saving my work. I am seriously considering moving to another browser (though not a Microsoft one). Please can you suggest something to help? I am on Windows 10 Pro Insider build 17074.

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Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

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Hi, hold down the Shift key when you start Firefox to start in Safe Mode. More - Diagnose Firefox issues using Troubleshoot Mode.

If any of your issues are fixed in Safe Mode, disable any theme or add-ons you have - Add-ons Manager (Ctrl+Shift+A) > Themes/Extensions and restart Firefox; then if it's OK, re-enable them one by one until you find the culprit. You may need to restart Firefox after enabling some add-ons.

You can also try reducing the number of Multiprocesses: Go to the 3-bar menu > Options (General) - Performance, then deselect 'Use recommended performance settings' and change 'Content process limit' to 1 or 2. See - Firefox's performance settings, and Startup, home page, tabs, and download settings.

Whilst in the 3-bar menu, you can also go to Options (Privacy & Security) - Permissions, and tick/check 'Prevent accessibility services from accessing your browser' then restart Firefox. More - What is the Accessibility Service Indicator?

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!