GPUI's RenderImage contract is BGRA (assets.rs) and every platform atlas
uploads the bytes raw into BGRA8 textures. All other decode paths swap
R/B before building a RenderImage; the PDF path fed pdfium's RGBA buffer
straight through, so PDF pages rendered with swapped channels on every
platform (white/gray unaffected, colors wrong).
Swap R/B at both RenderImage construction sites (page view + thumbnails)
and pin pdf_viewer's RGBA raster contract with a native channel-order
regression test (skips when no libpdfium is present).
yenru0
5ee6aa1e50