When page scrolling is enabled and scrolling down the page, the row context menu of RadGrid rows do not open at a correct position.
Demo: Video Recording
Testing conducted in Safari 13, MacOS
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It has been reported and confirmed that the same behavior happens with RadComboBox. If it's located somewhere on the bottom (out of the screen boundaries), the positioning of the DropDown element appears on the Top of the page instead of appearing where the ComboBox is.