As mentioned in bug 31278, currently convertToLayerCoords is ignoring transforms when calling localToAbsolute which looks wrong. This bug aims at removing this limitation.
Created attachment 107396 [details] Proposed fix 1: Pass true as useTransform and account for our layer's translation to avoid breaking the rest of the code.
Comment on attachment 107396 [details] Proposed fix 1: Pass true as useTransform and account for our layer's translation to avoid breaking the rest of the code. Looks like this patch only affects position:fixed elements. The bug title and change log should be updated to reflect this.
Created attachment 107414 [details] Proposed fix 1.1: Updated bug & ChangeLog.
Comment on attachment 107414 [details] Proposed fix 1.1: Updated bug & ChangeLog. Let's forget about this patch, the scope is not right: my understanding is that the rest of the code is still assuming that transforms are not taken into account in convertToLayer and it seems fragile to just patch one code path.