When tiled backing store is enabled but resizes to content is not, the scrollbars are not repainted correctly. There are three issues behind this. PaintsEntireContent is not set correctly on FrameView, painting is clipped to top of the docment and the scrollbar is painting at the top of the document.
Created attachment 206439 [details] Patch
Comment on attachment 206439 [details] Patch Qt has been removed, clearing review flags.
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