qt warning["qt.qpa.drawing: Display non non-main thread! Deferring to main thread"]

Hi . I'm starting to get concerned about this warning message.

qt.qpa.drawing: Display non non-main thread! Deferring to main thread

this message seems to occur load the qml.

Is this message a strong problem in createing a GUI?

I don't know why, but intermittently, a strange situation occurred where two dynamic application modal windows appeared in order, but the lower priority window went to the front.

If it is a problem, is there a solution?

please show me  sample example.