[ubuntu] Ubuntu 16.04 makes a program crash - certain Qt related bug... how to get help ?

First - APM Plaer 2 had this problem: https://github.com/ArduPilot/apm_plaer/issues/940
*only* on 16.04 , no other. distro we are aware of. the problem got a work-around.
now this problem spawned: https://github.com/ArduPilot/apm_plaer/issues/941

Again - only 16.04, reproducible on multiple systems.

I have no clue on how to proceed, how to bring some attention to this problem, as it's apparently a kind-of random problem, but very reproducible due to the nature of the log-loading that trigers it, other applications are most likely affected, but not that easy to reproduce.