Perform the suggestions mentioned in the following articles:

• Clear Cookies & Cache
• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems
• Update All your Firefox Plugins -> https://www.mozilla.org/en-US/plugincheck/
  • When Downloading Plugins Update setup files, Remove Checkmark from Downloading other Optional Softwares with your Plugins (e.g. Toolbars, McAfee, Google Chrome, etc.)

Check and tell if its working.

Thank you for your response. I should have mentioned in my original post that i have already performed those actions. I have even tried disabling all extensions and themes and still no luck with those sites.

As far as i can see, the browser is just not loading certain scripts that it has been fine with in the past.

-> Websites look wrong or appear differently than they should

Check and tell if its working.

I had the same problem... try this: click on Tools>> Add-ons >>Extensions >>Javascript Command ,make sure it is enabled ,or from the add-on bar at the bottom of the Firefox window click on JS ...also you can try to disable it then re-enable it .

Thanks for all the feedback. After much testing, including all of the above, it turned out to be some bug with the latest version of Kaspersky for Mac. I have disabled it for now and everything is running as normal.

I can finally give up Chrome and get back to FF!

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