New feature requests can be submitted here: https://input.mozilla.org/en-US/feedback

Thanks. I hadn't really looked for a request page.

Does this happen if you are closing multiple tabs?

When you close multiple tabs and leave the mouse pointer on the Tab bar then this should keep the tab fixed in position. One you move the mouse pointer from the Tab bar then this should correct.

Does this behave differently for you?

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: "3-bar" menu button or Tools > Add-ons > Appearance
• Do NOT click the "Refresh Firefox" button on the Safe Mode start window

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

I should've said "closing a tab". So say I have two tabs open. I select the x mark on the right tab. When it goes away, the left tab expands to where my mouse arrow is. Not so on Firefox. I think homeboy above got it and gave me the right answer. Firefox don't do this thing.

On another note: while I have "Warn me when closing multiple tabls" UNCHECKED, it still warns me. Gee whiz.....