I customized some Key Commands in Preferences to new keys on a new install of Dorico.
I noticed the mouseover tool tip shows the old keys, not the new ones.
I quit Dorico and opened again, and now it is ok.
So I guess the tool tips are not properly updated when the Key Command is modified/customized.
Speaking of Key Command oddities, here is another bug. I was operating without a network connection (or perhaps an invalid network connection) and needed to quickly know the current keyboard assignments, but Dorico was unable to do this normally: Help → Key Commands repeatedly showed an error because ‘localhost:xxx can not be reached’ . Something about this Help option requires a valid network device at some point. Very unHelpful in that particular situation.