The vCalendar plugin should have a possibility to open and import local .ics files. Best option would be to have a mechanism available, such that we can use 'Open with Claws vCalendar' on .ics files and/or have a DBus action to do that (maybe over the in the plugin already existing Calendar Service?). Also some import via GUI out of the plugin inside Claws of course would then make sense.
Hello, While not as user-friendly as what you describe, You should be able to right-click on the vCalendar root folder and use "Subscribe to Webcal" with a file:///home/user/.../calendar.ics URI, at least.
To be more exact, with importing, I mean adding the dates from the existing .ics to an already existing calendar, such that classical .ics files for a single date, which are downloaded from somewhere for a single event, can be added to a specific calendar in vCalendar. (I am aware, that I can register local files as separate calendar, through using the menu entry for WebCal abonnements with file:// protocol like e.g. `file:///home/jdoe/.local/share/orage/orage.ics`)