--- a/gfx/layers/wr/WebRenderCommandBuilder.cpp
+++ b/gfx/layers/wr/WebRenderCommandBuilder.cpp
@@ -943,17 +943,18 @@ Grouper::ConstructGroups(WebRenderComman
 
       // Initialize groupData->mFollowingGroup
       // TODO: compute the group bounds post-grouping, so that they can be
       // tighter for just the sublist that made it into this group.
       // We want to ensure the tight bounds are still clipped by area
       // that we're building the display list for.
       if (!groupData->mFollowingGroup.mGroupBounds.IsEqualEdges(currentGroup->mGroupBounds) ||
           groupData->mFollowingGroup.mScale != currentGroup->mScale ||
-          groupData->mFollowingGroup.mAppUnitsPerDevPixel != currentGroup->mAppUnitsPerDevPixel) {
+          groupData->mFollowingGroup.mAppUnitsPerDevPixel != currentGroup->mAppUnitsPerDevPixel ||
+          groupData->mFollowingGroup.mResidualOffset != currentGroup->mResidualOffset) {
         if (groupData->mFollowingGroup.mAppUnitsPerDevPixel != currentGroup->mAppUnitsPerDevPixel) {
           GP("app unit change following: %d %d\n", groupData->mFollowingGroup.mAppUnitsPerDevPixel, currentGroup->mAppUnitsPerDevPixel);
         }
         // The group changed size
         GP("Inner group size change\n");
         groupData->mFollowingGroup.ClearItems();
         if (groupData->mFollowingGroup.mKey) {
           MOZ_RELEASE_ASSERT(groupData->mFollowingGroup.mInvalidRect.IsEmpty());