QTableview with flat header

[AlexVhr]

Ah, so you are aiming for a maximum resemblance with the other cells. Then maybe try this style:

QHeaderView::section {
border-top: 0px solid grey;
border-bottom: 1px solid grey;
border-right: 1px solid grey;
background:white;}

QHeaderView::section {
border-top: 0px solid grey;
border-bottom: 1px solid grey;
border-right: 1px solid grey;
background:white;}

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You can experiment with styles in QtDesigner, by the way.