I have one horizontal and one vertical monitor, when pressing Ctrl+Alt+W
I notice, that the current active window is no longer active, nothing appears, but I am able to press →
and ↵
to move the window one workspace right.
At first I tought it didn’t work and pressed it a few times on different windows, budgie crashed and presented me a logon screen (I was logged out, since there is a different wallpaper for when I’m signed in.
https://github.com/ubuntubudgie/budgie-extras is the correct place to report this.
Just to say though, I cannot reproduce your crash on a single monitor. I don’t though have two monitors to play with.