The "New" marker above comments does not vanish in my theme. It is basically vanilla Bartik with some tweaks. The marker is hidden by default and inserted via JS according to this comment in comment.html.twig:
This seems to be working as the marker is displayed after loading. The problem is that it is always displayed even on repeated views of the article. I have investigated it for some time now. It appears that the AJAX call to /history/NID/read always returns the current timestamp, not the timestamp of the previous view. Returning the timestamp of the current request does not make a lot of sense to me.
Is my analysis correct so far? Should /history/NID/read return the last instead of the current? If that is true, what could be going wrong here?
Thanks in advance,