This is a known bug and discussed in https://veyon.nodebb.com/topic/100/broadcasting-and-screen-lock/7 already. We're working on a solution and hope to get this fixed in 4.1.3.
Can you try to set the log level to "debug" in Veyon Configurator and run "veyon-server" programm manually in a terminal on the affected client? May be the server crashes or there's some kind of timeout issue.
Thank you for your investigations! I opened an issue at https://github.com/veyon/veyon/issues/420 so we can do further investigations and finally fix the issue.
Do the integration tests report computer rooms and computers properly? If so, did you change the network object directory to "LDAP/AD"? (https://docs.veyon.io/en/latest/admin/ldap.html#using-ldap-backends)
Thanks for reporting! Veyon 4.1.3 will include a fix which trims spaces and newlines from host and MAC addresses automatically when editing them through Veyon Configurator.
looks like thumbnails resize nicely when I click on the Veyon notification icon twice. The first click minimizes the Veyon Master window; second click restores the Master window and the moniotored thumbnails get resized.
Oh, I also just discovered the slider and buttons along the bottom of the window - that's what I was looking for!