Editor - Unable to delete last line

It appears once the last line of script is an unfinished comment, those characters can not be deleted. You will also notice the strange error on line 1.
Ctrl-Z gets you out of the fix.

Hi Stephen,
Thanks for the catch! Can you give us a bit more information about your environment (what browser you’re using, operating system, and such)? Because the part about not being able to delete it doesn’t occur consistently. It would help us narrow it down if we knew what kind of setup you’re using.

thanks,
Uval

Hi,

I’m on MacOS High Sierra, version: 10.13.2 (17C205)

Chrome: Version 63.0.3239.132

Can I tell you any more?