Hi, thank you for reporting.
For the point of plasma-mobile not depending on plasma-dialer, I'm sorry that's a "wontfix": there are usecases (e.g. tablet) where plasma-mobile can be used without plasma-dialer, then it makes no sense for plasma-mobile to depend on plasma-dialer and to force some user to install plasma-dialer even if not needed.
Your point will be addressed in the near future, as a metapackage is being worked on to bring something like plasma-mobile-phone (which will depend on plasma-dialer and many others) and plasma-mobile-tablet (which will not depend on plasma-dialer) to Debian. In the phone usecase, you will have to install plasma-mobile-phone to get a full plasma-mobile system for the phone usecase, including the dialer.
For the point of the plasma-dialer error, that's an error I've seen in two situations: inside a virtual machine (hence no modem available to route audio calls) or when something was crashing really bad. Just to be sure, have you installed plasma-dialer from the Debian repo with all its dependencies, right? Does this error still happen after reboot?
Kind regards Marco
