Perspective viewport weirdness, for real

Ok, I posted once before about this & then I mistakenly thought I was able to repeat the problem but was actaully activating an unrelated feature. So, the problem is still the same: when I’m using the final WIP, several times a day the perspective viewport goes into a weird mode. The view continues to be a perspective view, but the mouse no longer does what it’s supposed to do. My RMB becomes Zoom instead of Rotate, and I can’t select objects in the viewport or change it to anything else. And, Shift+RMB becomes Rotate and CTRL+RMB becomes Pan. If I click out of Rhino and into any other program, then back to Rhino, that fixes it. But nothing in Rhino fixes it. Enjoy the video that I had to take with my phone (because activating a screen-capture program makes Rhino go back to regular behavior.) Please note that at the end of the video I open Irfanview on my other screen, which fixes the Rhino problem.

Hi Peter,
I have had similar behavior but I found out what was causing it accidentally hitting windows key plus space. I installed a German language keyboard installed in Language settings which I find for some reason, maybe hot key combos gets activated when I am using Rhino, completely changing how the keys on the keyboard work. When this happens I have to click on the icon and go back to English keyboard.

It’s a long shot but do have any other language packs installed under windows display Language/ preferred languages?

No, I only have English installed on windows.

Argh ok, I thought is was worth a try since it’s similar weirdness when it kicks on.

Well it might still be some sort of “accessibility” or other Windows shortcut being activated, I’ve had that happen. They usually make certain buttons “sticky,” stay pressed after you’ve let go messing up all kinds of things.

That sounds good. Could be the alt button, but why would it go away when I open another program & then come back? At first I was thinking maybe a keyboard malfunction - maybe it could still be. I’m just posting to see if anyone else has the same issue & I’ve heard nothing.