The permissions cannot be change before the packaging them because they are in Windows and it doesn't understands anything about the Linux permissions system. The permissions can be changed in the postinst script for .deb package.
Nop, I was wrong. The packager already solved that. I will make PR.
You did and it's merged. Solved. (ToDo: reference PR here.)
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Nop, I was wrong. The packager already solved that. I will make PR.