With backend as software(QT_QUICK_BACKEND=software)

If Rectangles with 1-pixel border or 1-pixel width/height is drawn on top of the rectangle background. Any updates triggered on the Background rectangle causing 1 px border or 1 px rectangle to vanish.

Note: Issue occurs when the Rectangle coordinates are in float value.

Reproducing steps on Sample APP:
1.On Application launch, Click the Press button.
Observe that the m_line Rect is missing and the borders of m_sqaure are not properly drawn.

2.Clicking on the m_mainRect brings back the borders and lines.

 Attaching images with and without issue and sample app to reproduce.