I have openHAB2 (version 2.5) running on a Pi, and a 7" Raspberry screen in the kitchen, showing HABpanel. This works reasonable well, and over time I found most of the reasons why something doesn’t work.
But once in a while, the HABpanel gets stuck. The time shown is no longer updated, the weather is not updated, nothing. Usually when HABpanel has no connection to the server, there is a small red message in the lower left corner, and the time still counts on. But in such a case the time is just no longer updated. The network between server and display is alright, I can login from one into the other. My usual “workaround” is to just power-cycle the display, and once it reboots it starts the browser again and everything works.
How can such a case be debugged? The display where this happens is just a display, there is no keyboard or mouse attached, so it’s kind of hard to do that, and then pull up any kind of debugging information.