Hey, circling back to this (thank you for your patience!) - I tested this out and found a slight issue: this only works to change to the next tab if the original pane was on the side of the screen. Otherwise the first move action doesn't do anything (behind the scenes it switches to the next pane, but the user doesn't see anything because it's hidden) and only then it switches to the next tab.

If you want to fix this, I'll be happy to take another look and merge.

Hey, I can't reproduce this. I tried with a horizontal layout with 5 panes. 1 at the row on top and 4 at the row below. Even If I start at one pane in the second row in between and switch to right the correct pane comes to fullscreen and changes.
Did you mean such a case or did I got you wrong?

Oh, wait - sorry! This was a misunderstanding on my part. When in this situation as you describe, the focus first switches to the other pane in the same tab (which then turns full screen) and then when it reaches the edge, to the other tab. I wasn't seeing this because I tested this with all panes being identical. My bad!

I don't know why we don't see CI running in this PR (probably because it's quite old). I'm going to run the tests locally on this branch and if they pass I'll merge - otherwise we can troubleshoot things here.

Everything's green. Thanks for putting this together and once again, thanks for your patience!