When pulling a tab into a new window and then opening a new tab, the first tab in the new window becomes hidden.

[Mordaedil]

Maybe this is possible to fix in the current version via some setting, but I've been unable to find it. I might have hit some unknown combination of keys that causes this issue to occur, but not been able to reverse it, so I put it here in hopes a solution can be suggested. It no longer is an issue if I disable this add-on, so I can only guess that they are related. Attached pictures of the problem.

Basically, the process to recreate is that I open a new tab, drag it out to make a new window. Go to a website in that tab and then open another tab by middle-clicking a link or similar. The new tab opens, but the old tab becomes hidden. If I go to the list all tabs tab, it shows up under Hidden tabs. This is undesirable behavior, as even if I bring up the tab from there, move it around, switching away from it causes it to go into hidden again.