You can select a link and then copy the link from the location field in the details. You can click the URL and use Ctrl+A and Ctrl+C to copy the URL to the clipboard.

Note that it should work if you select (highlight) multiple items in the media list and press Ctrl+C to copy highlighted items to the clipboard if the right-click context menu isn't working.

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

• Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

I started it in Safe Mode, but the problem was still there.

I see that you are on a Mac.

Did you try the Mac version with the Command key (Cmd+C)?

Can you click the location field and highlight the text in the field with the mouse?