HABPanel black screen, how to restore?

Hi, I was fiddling around with HABPanel, but now I get a black screen without any controls.

Tried to delete /var/lib/openhab2/config/org/openhab/habpanel.config, but no result.
Opening /var/lib/openhab2/config/org/openhab/habpanel.config gives me:

:org.apache.felix.configadmin.revision:=L"9"
lockEditing=B"false"
panelsRegistry=“service.pid=“org.openhab.habpanel””
service.pid=“org.openhab.habpanel”

Is there something wrong in the config file?

UPDATE: I pasted an example i found on the internet in the JSON panel registry
https://pastebin.ubuntu.com/23590783/

I can work with it, but once I remove the panel registry, it fails again