Finally!
I tried inserting after a recent update. They’ve never worked for me, see here. But I’ve seen videos about this app, and they work. So I don’t know what the problem was, but the app is now much more valuable to me.
As someone with not the best memory, an app like this is very important to me. I don’t record everything…”Dear diary…” LOL, just important events.

Curious as to what changed. The links look the same!
Today:
[""file:///home/bill/Pictures/Dogs/Diamond/signal-2024-04-16-180605_002"".jpg]
Old (didn't work):
[“”file:///home/bill/Pictures/rn””.png]
And no it’s not the PNG. I also tried a PNG, and… it works!