Once I execute some code from the Editor as a script, ctrl-A now highlights the script output while I have my cursor in the top pane. Even if the Script Output tab is not the active tab in the lower pane, it behaves the same. Once that happens, ctrl-A will not highlight/select anything in the top pane. If I select via some other method, the code is highlighted, but ctrl-C copies from the Script Output pane - which is really bizarre. This is beta .7
Fixed for next beta. If this is a blocking issue you can return to MDI mode in the meantime.