Date detection in mail.app intermittently not working

I appreciate the ability of the Apple Mail app to detect dates and times in emails - if only it would work reliably. It seems to stop working every now and then so that I have to restart the Mail app in order to get it working again. (Just to be clear: “stops working” I mean that hovering over a date will not reveal that clickable box that tells me that the date has been recognized as such. When I restart, the same date in the same email will show that box.)

Does anyone see anything similar? Is there a solution for this? Or should I just forget about this would-be feature? Because if it only works sometimes, I think I’d rather develop alternative workflows that don’t rely on it…

I’m on a Mac mini M1 and Big Sur.

Are you using a utility like PopClip or anything else that monitors the keyboard? I find that in some applications PopClip interferes.

Not on this machine, no.

Yes. Not sure what exactly counts as “monitoring the keyboard”, but if I go after which apps have access to “Input Monitoring” in System Preferences, then I have Karabiner, Terminal, OBS, and Touch Portal.

The latter two are not usually running when the problem occurs. I’d also assume that Terminal doesn’t interfere so it would be Karabiner that causes this. But how?

By “monitoring” I mean that Karabiner and the others might be watching the keyboard for input and that is triggering some interference with date detection. I have no idea what your configuration is, so I’m just suggesting you turn all off Input Monitoring for everything, reboot, then leave them off for a while to see if the date detection improved.

OK, since I’m not using Karabiner anyway, that’s an easy thing to try…