uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

Make sure you are not blocking content.

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?

Firefox 42+ has a Tracking Protection feature that is enabled by default in Private Browsing mode. Firefox shows a shield icon at the left end of the location/address bar in case content is blocked by Tracking Protection, click the shield icon for more information.

You can disable this feature in "Options/Preferences -> Privacy & Security" or via the about:privatebrowsing page that get when you open a New Private Window.

• Options/Preferences -> Privacy & Security: "Use Tracking Protection in Private Windows"

• https://support.mozilla.org/en-US/kb/tracking-protection-firefox
• https://support.mozilla.org/en-US/kb/control-center-site-privacy-and-security-firefox

See the Web Console for more detail about what content is blocked.

• "3-bar" menu button or Tools -> Web Developer
• https://developer.mozilla.org/en/Tools/Web_Console

Pkshadow said

uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

This did not resolve the issue. No change in behavior.

What happens when you run in Safe Mode as per Fred's instructions ??

Thanks for your help. Firefox updated when I restarted in Safe mode today, and the issue is resolved in both safe and standard mode. It is also working on other systems at the office.

Tried both solutions. With Fred's solution it works in safe mode, but when switching to normal mode I still don't see the captcha box

westi2002 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.

Hi TechieJim

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block (wanted) content (Adblock Plus, NoScript, , Discard, #Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block (wanted) content.

• make sure your extensions and filters are updated to the latest version

You see the shield icon at the left end of the location/address bar in case content is blocked by Tracking Protection.

• click the shield icon for more detail and possibly disable the protection
• check the Web Console for more detail about what content is blocked by Tracking Protection
• "3-bar" menu button or Tools -> Web Developer

• https://support.mozilla.org/en-US/kb/tracking-protection-firefox

The problem maker was Ghostery. Added as trusted site, problem solved. Thanks for your help

That was very good work. Well done.

I am on FF ESR 52.9 and since a few days I had problems with aliexpress logins and google captchas. Digging into my extensions I found that ghostery and randomagentspoofer cause the problem. Disabling either one of them did not help but disabling both and then restarting the browser brought things back to normal. Thus I think it is not mozilla to blame but possibly the extension providers. Ghostery was updated July 3rd but Randomagentspoofer is the same since 2016. So it could also be that the captcha programmers did change something in the background. In any case it is a constant struggle between users keeping their privacy and the advertising/tracking industry.