I’ve seen multiple notifications for “like” on a post here on meta:

Note the two arrows on the left indicate likes for the same post - where usually you only get one.
Also note the “solved” plugin notification in between (arrow on right) - perhaps it’s related?
「いいね!」 3
This may be a new bug somehow cc @sam
「いいね!」 1
riking
(Kane York)
3
This is the issue where the thread title changing causes a second notification to issue.
It’s a relatively recent regression.
「いいね!」 1
sam
(Sam Saffron)
5
Confirmed, I got one yesterday as well, will figure this out.
「いいね!」 1
sam
(Sam Saffron)
6
This has existed forever, it turns out … simple repro
- user A likes post
- user B edits post
- user C likes post
Double notification.
「いいね!」 2
sam
(Sam Saffron)
7
「いいね!」 8