Apple Mail attachment paperclip icon missing

I've not found this particular issue so I hope someone can shed some light. Apple Mail, Sonoma 14.7.4, MacBook Pro. Please refer to the screenshot (I hope it's clear). Sometimes in Apple Mail, the attachment paperclip icon shows up in column view, which is immensely helpful when I need to find a particular email (red arrow #1 - it shows an outbound attachment but inbound looks the same). But sometimes, it's missing (arrow #2) - even though within the body of the email, there are attachments. I've checked all the settings suggested in other discussions, and tried restarting Mail in safe mode (no difference). The only clue, perhaps, is that these problem attachments appear different in the body of the email, with their little down-pointing save arrows instead of images or icons. This isn't a big problem, as Mail works fine in every other way I want - but the lack of the paperclip indicator is a pain. Any insights? Thanks in advance!

[Edited by Moderator]