Does this happen every time when replying with the reply tool, or just once or twice? And did it ever happen when not using the reply tool?

We couldn't reproduce it, and I noticed that there were recently a few new reports of pages not being marked as read on the watchlist when expected (see the last few comments on T218511). Most likely this is not related to the reply tool, and just a part of that general problem.

In T321277#8333277, @matmarex wrote:

Does this happen every time when replying with the reply tool, or just once or twice? And did it ever happen when not using the reply tool?

We couldn't reproduce it, and I noticed that there were recently a few new reports of pages not being marked as read on the watchlist when expected (see the last few comments on T218511). Most likely this is not related to the reply tool, and just a part of that general problem.

It happens to me frequently, and not just on my watchlist. Let's look at my last edit https://commons.wikimedia.org/w/index.php?title=Commons_talk:Abuse_filter&diff=698399540&oldid=698385093 , dated 05:20, 23 October 2022 EDT -0400 (09:20, 23 October 2022 UTC) and purposely made with the DiscussionTools Reply tool in contemplation of this post. On the revision history https://commons.wikimedia.org/w/index.php?title=Commons_talk:Abuse_filter&action=history&dir=prev&offset=20221018000621%7C697063215

On the third hand, it did not happen with my next edit https://commons.wikimedia.org/w/index.php?title=Commons:Administrators%27_noticeboard/User_problems&diff=698405102&oldid=698403797 .

Here is how that 05:20, 23 October 2022 EDT -0400 (09:20, 23 October 2022 UTC) edit looks on my watchlist with grouping.

It happened again with edit https://commons.wikimedia.org/w/index.php?title=Commons:Help_desk&curid=523680&diff=698609678&oldid=698605975 00:49 24 October 2022 EDT -0400 (04:49 24 October 2022 UTC). Note also that there are three other edits to the Commons Help desk that falsely show as "updated since your last visit" too.

It happened again after I turned on some dark CSS for Vector, in edit https://commons.wikimedia.org/w/index.php?title=Commons:Village_pump/Copyright&diff=698673568&oldid=698672727 06:18, 24 October 2022‎ EDT -0400 (10:18, 24 October 2022 UTC), and one three minutes earlier.{F35619890}

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It happened again in edits https://commons.wikimedia.org/w/index.php?title=Commons_talk%3AAbuse_filter&type=revision&diff=699102201&oldid=699053187 , but not all of them were using the reply tool, some were using https://en.wikipedia.org/wiki/User:BrandonXLF/QuickEdit.js .
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