Popup appears in second screen in Linux

[martinszy]

Hi, I'm using Mint Linux and the tab previews appear in my second screen, around the same position they should appear in the main one.
I have positioned my second screen "above" the main one in the screen configuration, this may have someting to do with it.

Firefox: 44.0.2
Tab Scope: 1.6.2.1-signed

I'm disabling it until it becomes usable again

[dev-coder]

I have the same trouble at times (not always) and I use dual monitors running Windows side by side though. Once it opens on the wrong window even closing and restarting firefox doesn't seem to fix it. A log off or reboot does though. Not sure why it sometimes happens and not other times.
In my specific case I usually run firefox on my 2nd monitor (on the right). But these wrong placed popups show up on the left.
And this occurs whether I have the pop-up location set to "below tab" or "auto".