Homebridge package seems to run, but I can’t open the UI
Sorry to bother again, but I now managed to upgrade to DSM 7.1.1. and was able to install Homebridge. Though, and I do suspect it might be connected to node.js v12 still being present on the machine, the GUI does not open but the connection gets refused (ERR_CONNECTION_REFUSED).

I am hesitant to uninstall Node.js 12, because there are several important services connected to it, especially Synology Drive. I installed node v16 and 18, so I have three versions running in parallel, but to no avail. 

Is this even the real cause of the problem, or am I on the wrong path? Any help is very much appreciated!

P.S.: The firewall is open, of course, and SSL is enabled. 