When the Linux client is on a Wayland system we sometimes get a bad mouse cursor. We've seen it with the standard I-beam cursor on Windows, but there might be others.
Instead of the correct cursor we get two thick vertical bars, not unlike a pause symbol. It doesn't seem to be a simple inverted version of the I-beam though as there isn't any pixels at the top and bottom.
The cursor starts working if any pixel is changed from alpha having 00 or ff, so there seems to be some heuristic somewhere that detects simple cursors like this.
I can reproduce the same bug in Firefox using the same cursor. Not quite known why rdesktop is unaffected under the same circumstances.
Seems to be related to the size. rdesktop has a lot of padding around the cursor, expanding it to 32x32 pixels. Doing the same in Firefox gets a working cursor.
Found the bug in Xwayland:
So either we ignore it until they've fixed it, or we do a workaround (e.g. pad to 8 pixels wide).
We trust that upstream will roll out the patch they have suggested on the upstream bug entry.