Avogadro 2 1.98.1 Select Menu Select By Atom index crashes the app

To reproduce this bug type some arbitary atom index which is not present in the current atoms.
The System crashes!
This bug is similar to the bug of **Create New layer from Selection ** crash bug.

Thanks. Yeah, that’s because you don’t have any atoms.

Should be some easy bugs to fix - those methods should check to see if the molecule has atoms and if not, just return.

BTW, I definitely appreciate the testing / bug reporting. It’s always hard to come at an app with “I’m going to try everything”

Okay, here’s a fix: