This is not the atitude an open source developer should have toward the community: publish the standards, specify them. Open source software's, or more clearly, libre software's (although I understand that Apache 2.0 License is a lesser general license, not those copyleft ones.) purpose is to make things open and reproducible, not just irresponsibly marking all unofficial builds unsupported and even trying to build a barrier to stop any other people packaging unofficial versions of the software. The developer is violating the core values of open source.
I mean, if you're making a fork, don't use the name of the project you're forking. If you fork Firefox and call it Firefox+ for example, Mozilla's legal department will email you, and ask you to stop violating their trademark.
unbelievable
This is a misleading title. Trademarks were only mentioned in passing, as they appear in the Apache 2 license.
The more interesting thing here is an open source project that has upstream legal obligations and cannot support build from source due to official credentials needed to enable certain auth methods.