Bugzilla

Got a fresh display list dump from the Pernosco recording.

Analysis so far, based on IDs from this dump:
 * We have a container layer 0x55d747051e80 which has three scroll metadatas, for scroll ids 7, 6, and 5.
 * We have a container layer 0x55d746c40420 which has one scroll metadata, for scroll id 6.
 * These are siblings, their parent is a container layer with scroll metadata for scroll id 4.
 * The first layer's branch in the scroll node tree yields the scroll parent chain 7 -> 6 -> 5 -> 4, the second layer's branch yields the chain 6 -> 4. We get an assertion because 6 has conflicting scroll parents.
 * Both container layers come from `nsDisplayScrollInfoLayer` display items. For such items, the bottom-most metadata comes from the item's `mScrollFrame`, and the remaining ones are based on the item's ASR chains.
 * Looking at the two items' ASR chains, they are indeed (6, 5, 4) and (4), respectively. This seems wrong; the second item's ASR chain should be (5, 4).

Got a fresh display list dump from the Pernosco recording.

Analysis so far, based on IDs from this dump:
 * We have a container layer 0x55d747051e80 which has three scroll metadatas, for scroll ids 7, 6, and 5.
 * We have a container layer 0x55d746c40420 which has one scroll metadata, for scroll id 6.
 * These are siblings, their parent is a container layer with scroll metadata for scroll id 4.
 * The first layer's branch in the scroll node tree yields the scroll parent chain 7 -> 6 -> 5 -> 4, the second layer's branch yields the chain 6 -> 4. We get an assertion because 6 has conflicting scroll parents.
 * Both container layers come from `nsDisplayScrollInfoLayer` display items. For such items, the bottom-most metadata comes from the item's `mScrollFrame`, and the remaining ones are based on the item's ASR chain.
 * Looking at the two items' ASR chains, they are indeed (6, 5, 4) and (4), respectively. This seems wrong; the second item's ASR chain should be (5, 4).