Prevent tab from shifting to a new window
This is an old problem, there was a add-on that fixed it, but that is no longer available, so the problem exists again!!
The issue is, you click on an existing tab to view the content, but (randomly) instead of opening the tab Firefox moves the tab to a new window, so now you have the hassle of closing that new window you didn't want and restoring the tab in the old window where you did want it!
A fix?? published is to change the setting (preferences#general) Under "Tabs" uncheck "Open new windows in a new tab instead" but that is a rubbish fix, it is turning off a function I do want to disable a apparently unrelated function I do NOT want.
So how do I prevent tabs being randomly teared off to a new window AND retain the functionality of "Open new windows in a new tab instead"
Alla svar (4)
Something strange about your jumping Tabs. I would suggest it is your mouse clicking and dragging that causes the issue.
This is covered on Options --> Tabs
The later you can click on the new window or the top of the tab and hold the click and drag it to the other window. Look for a vertical line in the tab bar before releasing the click to add the tab next to the one you hover over.
To prevent the new tab from opening a new window you can change this in the settings.
- Click on [about:preferences#general]
- Under "Tabs" uncheck "Open new windows in a new tab instead"
Note that you can drag the tab from the new window back to the Tab bar in the original window if you accidentally initiated a tear-off (Move to New Window). Firefox should close the window automatically.
When you say random, could you consider whether it might be that you're triggering the "tear-off tabs" feature? It doesn't take much to click and drag the tab down enough to launch it into a new window and if you're working fast, it's an easy thing to do. As cor-el notes, unless a new add-on comes along, you can manually "re-attach" the tab from where it was "detached" by making the new window resizable and dragging the tab to the tab bar in the other window.
While extensions cannot prevent a tab from being torn off, they can detect the change and put the tab back. Here's one that does that -- I haven't tested it myself:
Disable Tab Detach by Matt Hensman https://addons.mozilla.org/firefox/addon/disable-tab-detach/