[Webextension Regression] - Calendar invites not handled by calendar

[dugite-code]

This was a regression introduced with the migration to webextension. ICS files are extracted but not accessible directly via the standard Calendar accept/decline interface.

[vsessink]

The bug says "closed" but I'm still seeing ".ics" files instead of just the "Lightning" interface showing an invitation. On Linux, luckily, Thunderbird proposes to open this ics-file with Thunderbird, importing the invitation. However MacOS wants "CalendarFileHandler" to open it - delegating calendar management to Apple Calendar.
This is with Thunderbird 115.6.1 with Lookout 6.1.

[dugite-code]

Yes the previous issue was a bug in the implementation and was closed as it pertained to an old version of the extension. The new issue is a regression and a new method is required to achieve a similar result as was done in the past.