Unable to drag/move icons on Ubuntu 22.04 desktop

Ubuntu 22.04.5, gnome 42.9, wayland.

The problem I’m asking about just suddenly began today, I can’t figure out what triggered it.

Up until today I was able to drag all desktop icons around with no problem. Now today that is a problem.

I have my settings set to put new desktop icons on the top right corner of the primary monitor. That works fine. But now, if I try to drag one of those icons elsewhere on the Ubuntu desktop, it drags there, but it immediately snaps back to its original position and refuses to be moved elsewhere. I don’t know how else to describe this problem, it is as simple as that.

Under “ding” in gnome-tweaks the “keep arranged” setting is off, and I have the “Desktop Icons NG (DING)” gnome system extension enabled, if any of that matters.

Strangely, this problem does not exist for - I don’t know what to call them - “default” (??) desktop icons: Home directory, Trash, etc. Those I can drag around and place them wherever I want, as expected.

Another strange thing I noticed at the same time that this problem arose: If I put two files of the same type on the desktop - e.g., two *.png image files - a mysterious folder icon appears with a blue downward pointing arrow at the top left of that folder icon, the label of that icon is (in this example) “png”. If I left click on it, the two *.png image files disappear from the desktop, and if I left click on it again they reappear. If I right click on it, a message appears that says, “Stack this type”. Never saw any such thing before.

I need help understanding what is going on and how to restore the expected functionality to move all desktop icons around on the desktop. And to stop this strange “stacking” thingy that is appearing on my desktop.