Creating QProgressbar and styling it with border-radius results in broken progressbar when low value is set. That is, when the value is not large enough to at least paint a circle as a progress, it is instead ignored completely and rectangular progress is painted on. This becomes non-issue with large enough value. See attachments for example. 

I am creating this bug in spite of QTBUG-50919 as it doesn't seem to have any attention, probably because it is reported for the 4.8.x line and I have no other way of bringing this to your attention.