My suggestion is to have the transport panel in the bottom part of the project window also in the editors (key editor, score editor, etc) so we can avoid the floating transport bar!
Thank you
There is a transport panel available for the project lower zone. Access it by clicking on the down arrow in the “Setup Window Layout” section in the top toolbar. It is not 100% the same but, for me, it allows me to not have to use the floating transport panel while in the project or any editors.
Regards 
Please have a look here , but yes transport on editors bottom zone would be definitive solution.
@prock, I think lucatron is talking about editors opened in a separate window, then if you hit a transport button in the project lower zone, the separate window gets invisible behind the project window (on single monitor setups).
+1 for the OPs request and a good workaround was presented. 
Regards
Yes, I was talking about editors in separate window! your link, anyway, seems a good alternative!