Thanks for the suggestion @J-Hilk, I tried switching to gcc... and back to msvc.
Switching the build tools did not change anything (I currently do not have another platform installed, but I can try that later).
I still see JavaScript/QML QtQuick import annotation errors in 5.13.1 (but not if I switch back to 5.13.0 which is still installed):
Anyone else out there seeing anything similar when updating to 5.13.1? ?
(the weird thing is there is no complaint about:
#import QtQuick 2.13 (it's only the other #import lines that display an error).
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