"U" as single key accelerator in new Acrobat gives text underline not highlight tool

Awesome. Will do.

Can you also do anything about the radical instability of the new acrobat? Resizing windows when more than one document is open causes the application to stall (beachball), freeze, or crash. It is hugely annoying and ruins anyone's workflow. I repeatedly have to force quit (losing saves) and restart. I have been reporting this for months now, no uptake. It could be a caching issue; but I have heard that Acrobat's window sizing may be problematic for whatever reason. Frankly, this is far worse of a problem than the u=highlight tool (which works now, btw). I'd consider it a highly urgent priority, an existential one for me in fact.

I've interacted with engineers from Adobe on this, have sent logs, etc. (all to no avail). Just try for yourself: load up 3 or 4 documents in Acrobat DC Pro (Mac) and try to move or resize the windows. You'll see what I mean. Check your Activity Monitor and you'll see that Acrobat is hogging huge CPU amounts (percent and time) when it's trying to respond to the window redraw.  (I'm using the latest MacOS with an M1 MBP; it's loaded with RAM and power, so that is not the issue.) Word documents are a snap. That is how Acrobat should be too.

Thanks.