Is this with all websites/pages, some, a few? [https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode Start Firefox in Safe Mode] {web link} A small dialog should appear. Click '''Start In Safe Mode''' (not Refresh). Is the problem still there?

I assume that this is about the location bar.<br>Something got changed there when it comes to copying the URL because the first click doesn't actually selects, but merely highlights the content.<br>A double-click works like in other text fields to select a word and a triple-click selects all content to allow reliable copying to the clipboard.<br>If you see a cursor in the location bar then a paste should work immediately. Start Firefox in <u>Safe Mode</u> to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if <u>hardware acceleration</u> is causing the problem. *switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes *do NOT click the "Refresh Firefox" button on the Safe Mode start window *https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode *https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems