Notifications for non-trivial edits were added a while back, with a special rule for edits made to code within a post on sites where code is treated specially:
a non-trivial edit is one which changes at least 10 characters (this is using a diff algorithm, so it's not a simple add/delete; and is naturally a little fuzzy). For the "technical" sites (where code highlighting is enabled) changes to code of at least 2 characters are considered non-trivial.
In addition to lowering the bar for being considered "non-trivial", edits to code were also called out explicitly in the notification itself. However, with the relocation of these notifications to the inbox, this distinction appears to have been lost:
I probably wouldn't even have noticed this, except that the old notification is still displayed on mobile:
This seems like a regression; since the information is available, it would be nice to have that noted in the full-site notifications as well.