Hi, and welcome!
For coding questions, please see the FAQ: What's a reproducible example (`reprex`) and how do I do one? Using a reprex, complete with representative data will attract quicker and more answers. This isn't one of them, of course.
My poor eyesight made it difficult for me to see exactly what's going on, so I'll ask. Is the desired behavior to move the highlighted block on stop to the right?
I'm on macOS, also, and what CMD I seems to do is to do is outdent to the left, up to the left margin, identically to SHIFT TAB. What I'd like to be able to do is what I'm used to in Sublime Text, say with CMD ] and CMD ] back and forth. Until tonight I didn't discover that I can with something that seems like it should be destructive, highlight and TAB [not CMD TAB as I said earlier]