Make sure that you do not start Firefox with the -no-remote command line switch. You can check the target line in the Firefox desktop shortcut. If you use this switch then you can't open an external link in this Firefox instance. You normally don't use this switch with the default profile, but only use it to open additional Firefox instances (or other versions) with their own profile and run them simultaneously.

• https://developer.mozilla.org/en-US/Mozilla/Multiple_Firefox_Profiles
• https://developer.mozilla.org/en-US/Command_Line_Options

Thank you for the reply;

The shortcut to Firefox doesn't contain any switches, and this is the only Firefox browser on my machine.

Do you know have any more ideas on what could be going on?

thank you

If you have a MOZ_NO_REMOTE environment variable then remove this variable and do not change its value to 0 because that doesn't work (Firefox checks for its existence and not the value). See "Windows Control Panel -> System"

cor-el;

Thank you very much for your help, your last reply led me to look around FF, so I used the Help -> Troubleshooting information -> Refresh Firefox... and that did it!

Again, I appreciate your help. Thank you very much, Ghayth

I have iMac OSX 10.14.6 and Firefox 68.0.2. Since the last Firefox update I cannot launch external links into Firefox if Firefox is not already running. When I try to launch the link Firefox does start but only displays a blank tab. If I then click the link again (now that Firefox is running) the link works fine. Sorry but I don't understand the reference from cor-el earlier about MOZ_NO_REMOTE Firefox is my default browser. Any advice most gratefully received.

I should have read this thread more carefully! I just tried Help -> Troubleshooting information -> Refresh Firefox and it worked for me too!

Many thanks cor-el and sorry I missed that first time looking at the thread.