What items do you see in the context menu of a tab?

Can you move the tab to another window?

Nothing pops up when I right click. NOTHING. NO menu.

I could move it to another window, but still cant pin it in another window. (That's how this whole thing started...I accidentally opened it in another window...dont even know how.)

Can't you pin any other tabs as well?

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

No, can't pin any tabs. Will try safe mode.

Safe mode worked. Thank you.

If it works in Safe Mode and in normal mode with all extensions (Firefox menu button/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via *"3-bar" menu button > Exit (Power button)

• Windows: File > Exit
• Mac: Firefox > Quit Firefox
• Linux: File > Quit

cor-el said

If it works in Safe Mode and in normal mode with all extensions (Firefox menu button/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears. Close and restart Firefox after each change via *"3-bar" menu button > Exit (Power button)

• Windows: File > Exit
• Mac: Firefox > Quit Firefox
• Linux: File > Quit

This makes no sense. How does one create a pin tab in Firefox using a Mac computer?

Did you try to open a new window to see if you can pin tabs in the windows?