[joezydeco]

I'd need to catch up with what happened in the BMW i3 case to understand what your obligations are to people that don't own the actual target device. At minimum, you provide a link to a repository you control with the vanilla Qt source. That should satisfy the requirement, right?

Installation of a modified library would seem (to me at least) to be a method you can share only with authorized owners.

I've released Qt products under LGPL, but they're all industrial equipment and I've never had a customer give any of this a second glance. They just want their shit to work.