Until a few weeks ago, I could use:

and it would bring a notification "popup" with the image. Now they just show the literal text in popup.

Tried with notification-daemon, lxqt-notificationd, dunst and xfce4-notifyd. Also tried to test with mate-notification-daemon, but it's just segfaulting for me. Somehow fixed the segfault, but nothing. Also tried some daemon from the "uikui" DE and notify-OSD.

Debian "bookworm," openbox WM/"DE," xorg. Liquorix kernel? I don't think a otherwise finely working non-stock kernel could explain it... could it? Seems too specific. Well, that I can test easily, I still have at least an older stock-one. Yep, apparently it isn't a kernel issue, unsurprisingly.


Downgraded libnotify4 and libnotify-bin to the outdated old-stable version, and still no images like I used to have. I guess there must be a somewhat cryptic additional package/library that adds this feature, without having it obviously implied in its name or stated on the description, that went missing in the upgrades for some reason.

I figured out the "solution." The command should be something like this:

So, the command in the original post lacks the explicit "summary/title," but it really does not, without it, notify-send interprets the body as the summary, but it can't have images there.

I don't know whether there was some recent change in libraries/programs, which previously either assumed that the formatted text block wasn't a summary/title, or "merged" the "-a" part with the summary/title... or yet, maybe I had the summary/title part set and removed in my script, although it doesn't quite look like that from the commented left-overs. But it's even perhaps the most likely explanation, my own mistake.