-used for things like macOS "lookup" a word to highlight it, probably would be in wrong place if done on a word in an oop iframe while pinched zoomed, which is a rare combination. Not sure what else this code is used for. Low priority to fix for now.
-I don't know much about this, in contact accessibility team about these
-either correct as is or fixed by bug 1732600 (displayport/apz related code)
-all of these are the basic code to set/get resolution except PresShell::CreateRangePaintInfo which was specifically made to work with fission in bug 1712400
-either correct as fixed by bug 1732600 (displayport/apz related code)
-ScrollFrameHelper::GetAvailableScrollingDirectionsForUserInputEvents resolution used to determine if scroll frame has at least one half pixel to scroll-> low priority to fix for now.
-nsHTMLScrollFrame::TryLayout, code inside an if checking presShell->GetMobileViewportManager() which is only true for root content documents cross process
-GetPaintedLayerScaleForFrame, fix in bug 1732660
-ScrollFrameHelper::RestrictToRootDisplayPort, use is inside if checking IsRootContentDocumentCrossProcess, okay.
-ScrollFrameHelper::DecideScrollableLayer, code is correct, if local resolution is 1 then nothing to do, okay.
-ScrollFrameHelper::SaveState code to just save/restore resolution, okay.
-correct (bug 1724808 fixed it)
-just used to get and restore resolution, seems fine.
-VisualViewport::Scale other browsers match our behaviour of returning 1 for subdocuments, okay.
-used in privileged test code only, okay.
-I think the use here only matters for top level image documents -> okay.
-these only get created for root content documents cross process, okay.
-used only for android -> look at for fission android, okay for now.
-ConvertToScreenRelativeVisual, this function has fission specific code (TryInferEnclosingResolution) so likely already audited for fission, okay.
-ViewportUtils::GetVisualToLayoutTransform, this function converts from visual to layout coords, so if the enclosing presshell is not the root content document then we don't need to access to the resolution. botond can you confirm?
-nsDisplayStickyPosition::UpdateScrollData only used for root content document cross process -> correct.
-nsDisplayTransform::ShouldPrerenderTransformedContent, hiro could you comment?