Changing surrounding characters at the end of a line leaves an instance of the old character.

[jackcasey]

Here I am putting my cursor inside the string s = "hello" and pressing c s " '.

I can't track this down to a package or anything in particular, though I assume it's related to the way atom will give you matching character pairs by default as you type (apparently regardless of language/grammar.)

Note that this behaviour is the same for quotes and brackets etc.

Sorry if I'm missing something obvious, that seems like a distinct possibility given noone else seems to have reported it yet.

[reverland]

The same problem. Fail to find out why now