One possible reason for this is, if you have the mouse pointer on a tab and you click and pull downward, Firefox will move it to a new window. This feature is called "tear off tabs." I don't know if there is a way to turn it off. There used to be at least one add-on that blocked it, but the one I knew about is gone now.

I have this problem too, and it's very irritating. Most of these shortcuts that "fix" stuff for me more often than not are a nuisance that creates problems. These are NOT features, they are useless. I know what I need, which is not what some hotshot programmer who left the real world years ago thinks I can use.

Hi D1005, can you tell whether this is caused by dragging downwards on a tab and triggering the "tear off tabs" feature? If you think that feature is too sensitive and needs a way to be turned off, you can provide your feedback using one of the following:

Feedback: https://qsurvey.mozilla.com/s3/FirefoxInput/

You also could try to drum up support for a change on social media, for example:

Facebook: https://www.facebook.com/Firefox Reddit: https://www.reddit.com/r/firefox/ Twitter: https://twitter.com/firefox

I honestly can't say what I'm doing. There are simply too many shortcuts that are too sensitive. Computers today are always "fixing" things for me, which takes me an hours to undo. Great for the geek who makes a living writing code, but unneeded and undesirable to this average user.

I wish I could go back to Windows 3.1 or equivalent, it would make for a higher efficiency of my time.

I don't waste time on any social media. My security is more important to me that any gossip page.

I did leave feedback. I always leave feedback.

Hi D1005, next time you notice this, try moving the tab that sprung into its own window back where it came from:

• if the new window is maximized, double-click the top bar to make it resizable
• pull that window down the screen a bit if needed to see the tab bar where it belongs
• click on the lone tab in the window and drag it to the tab bar where you want it to go: a thick upward-pointing arrow should show where it will drop when you release the mouse button

Hey jscher200, thank you! While this doesn't "cure" my problem, at least I can get the tab back to where I want it. Well I assume so, I'll have to try next time it happens. It's not real often, but often enough to irritate the heck out of me! I've tried a couple times, but never found the exact sequence of motions to make it happen.