The note for "Show tray icon" says "Does not work in all desktop environments." Fair enough.
However, this worked in Cinnamon on Linux Mint 19 but does not work on LM 20, neither Joplin 1.3 nor 1.4 pre-releases.
Kindly fix, please.
It's an upstream bug with electron. It's apparently been fixed We're waiting for the electron to stabilize a bit before upgrading. It will be fixed eventually, but there's nothing to do to push it forward faster, just need to wait.
It worked for me on the Mint 20 beta but not the subsequent release. Then after a Mint update a little while back, the tray icon started appearing again. The computer is running Joplin 1.3.18. So it seems that the tray icon can work on Cinnamon. Very strange...
1.4.11 includes Electron 10 and, as predicted, fixes this issue.