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Key strokes in upper case not in Caps Lock, lower case in Caps Lock, intermittant.

  • 5 cavab
  • 2 have this problem
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  • Last reply by PaulTH

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Firefox 45.0.1 Win XP SP3. While browsing various web sites, for short periods of time (up to several minutes) keystrokes produce capital letters when not in Caps Lock and small letters with Caps Lock on. During this same time, my Logitech wireless mouse clicks produce erroneous responses. The symptoms do not occur when using the keyboard/mouse on non-browser apps., the desktop, task bar, or start menu, but return when Firefox browser is put back in focus. I have not found a way to stop the symptoms, but have found ways to navigate some things, (e.g. Yahoo mail) in spite of them. Log on passwords are impossible though because I can't see what's being entered. The problem stops as suddenly as it begins and I can see no pattern to its occurrence.

Firefox 45.0.1 Win XP SP3. While browsing various web sites, for short periods of time (up to several minutes) keystrokes produce capital letters when not in Caps Lock and small letters with Caps Lock on. During this same time, my Logitech wireless mouse clicks produce erroneous responses. The symptoms do not occur when using the keyboard/mouse on non-browser apps., the desktop, task bar, or start menu, but return when Firefox browser is put back in focus. I have not found a way to stop the symptoms, but have found ways to navigate some things, (e.g. Yahoo mail) in spite of them. Log on passwords are impossible though because I can't see what's being entered. The problem stops as suddenly as it begins and I can see no pattern to its occurrence.

Chosen solution

It is possible that some of the status keys have the wrong state and Firefox sees them as still pressed.

Try to press all the status keys (Shift, Ctrl, Alt) a few times to see if that helps to recover from this. If it doesn't help then close and restart Firefox or reboot the computer.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools > Add-ons > Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
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All Replies (5)

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I'm on Firefox 46.0.1, not 45.0.1.

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Seçilmiş Həll

It is possible that some of the status keys have the wrong state and Firefox sees them as still pressed.

Try to press all the status keys (Shift, Ctrl, Alt) a few times to see if that helps to recover from this. If it doesn't help then close and restart Firefox or reboot the computer.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools > Add-ons > Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
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Thank you cor-el. I'll do as you say next time it happens. So far today it hasn't. Paul

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Thank you cor-el. I have tried your suggestion about pressing the status keys when the problem occurs and it does seem to work, at least for restoring the mouse to normal operation. I suspect it will resolve the upper/lower case keystroke trouble as well, but just haven't thought to test that when the mouse symptoms started. This does seem to be related strictly to Firefox though because when the problem is occurring, it disappears when I click the task bar start menu, invoke another application, then reappears when I put the browser back in focus. I'll try to remember to use the next failure opportunity to do more testing and provide more information.

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Thank you again cor-el. Now I know that it is a problem with my PC and is not a Firefox problem. It finally happened while I was using another program and Firefox wasn't even running. I now suspect it to be my keyboard. They're cheap enough, so I'm going to get a new one to see if this proves to be the case. It is strange though that it seemed until now to only happen in the browser. Maybe I'm spending way to much time on the internet.

BTW, how do I close out a resolved issue?

Paul