I installed Cryptomator from the ‘deb’ file in stable Debian 9 (stretch). Everything worked OK.
When I upgraded to Debian testing (buster, debian 10) I could not find the app via a search in Gnome. I reinstalled it and could find, open and use it OK. But I have two problems:
After a certain amount of time–perhaps after running a software update–I can no longer find Cryptomator again, and I can fix by reinstalling it from the deb package.
There is no system tray in Gnome 3.26, system tray has been deprecated, so I lost the ability to control the app that way.