Bug introduced in V10.0 and resolved in V11.3
(These are guesses. It is likely to have been resolved in an earlier version V11.X, but V11.3 is what I have access to.)
I am running Mathematica 10.0.1 on a four-year old iMac running OS 10.6.8. The following irritating behavior occurs regularly: I have a list with parentheses, and later on I need to add something to an earlier part of the list that involves quotation marks. As soon as I include the quotation marks, the matching between the parentheses gets lost, and I need to go in by hand to fix the parentheses matching. See the gif below for an example.
This also happens in version 10.0.2.0 on a 2014 MacBook Air running OS 10.10.4. I have verified that this does not happen in Mathematica 8 on the four-year old iMac.
Is this problem reproducible in general? How do we fix it? Is it already fixed in a later version? If so, is there a work-around without upgrading? Should this be reported as a bug to WRI?