I got this strange improper display of navigator with jagged red lines if during form load event

main Tab page, mTbPage.select() were executed
and no looping thru the DGV Columns like (even nonsense logic as below)
foreach ( DataGridViewColumn colun in myDgV.Columns)
datagrid columns were not looped through in form load
}

I know Main Tab page should not be explicitly selected, it will be selected no matter what other tab page were selected during form load . So that what it seem so far.


Hope this post may help some people to track down this strange display bug