This is just one of those things that I’ve looked and looked for, and can’t find, while it sits right in front of me. 

There is a feature, activated by a keyboard command, that enlarges the currently selected track, and makes all others very small on the screen.  What is this feature called - - so that I can disable, or assign a different command to it?

When editing, I hit it all the time by mistake when I’m going for Ctrl +Z - - which is simply “undo” the last edit. 

Thanks!

Re: key kommand kwestion - - kewbase

I think you are probably referring to “Zoom Tracks Exclusive”, which can be made to happen by hitting the “Z” key or Ctl+ down arrow. In any case, you can c/o your Zoom key commands in File menu> Key Commands> Zoom.............frank