See comment in QTBUG-42115:

"
Mostly irrelevant qWarnings is IMO a problem when developing, as we use QT_FATAL_WARNINGS to catch issues early (or just to trigger a stacktrace at the correct place), but that is a useless tactic when it triggers already at startup.

Is it really ok to print warnings in what Qt appear to otherwise consider a normal environment? And if yes, is there some way to suppress these specific qWarnings?
"