Harder to change focus in Combine as Tabs view, in v21.5 (Windows)

I am having a weird issue on Dreamweaver v21.5 (Windows) that is severely affecting my ability to work. This did not happen in v21.4 or earlier.

I typically work with two tabs open, in "Combine as Tabs" view. See attached screengrab. 

Now, in order to successfully change focus, I now have to click in the "Design" pane up top, or the tiny target of the title bar. And then to edit code I have to click again, in the lower, "Code" pane. Before v21.5, I could just click on either of the two Code panes to switch focus between the two pages.

Note that the pane on the left is currently the frontmost page, as indicated by the title bar being white instead of grey. BUT... counterintuitively, my cursor is actually in the page on the right (you can't see it on this screengrab, but it's on line 3), and if I type code it will appear in the page on the right.

So, while I am typing, I would normally expect any keystrokes to affect the page on the right, where I am typing. Just like in any app. I would assume, without looking at the title bar, that the page where I am able to type, is the one in focus. This is how Dreamweaver behaved for me until yesterday.

But if I were to invoke a keystroke, like e.g. Ctrl-H or Ctrl-1, it will affect the OTHER page, because it is actually in focus, not the one in which I am in fact typing. I then have to go out of my way to change focus, in order for keystrokes to behave as expected.

This is driving me crazy and slowing me down. Thank you for any help you can provide.