Confirmed in 25w32a.
Confirmed in 1.21.8 and 25w31a. I have also noticed that the bug is directional: if the water is refilling from the south and the east it will not happen, but from all other directions it will freeze as it is refilling.
Confirmed in 1.21.7. I would also like to request ownership of this bug (I am the original owner before it migrated) so that I can continue updating it.
Confirmed in 1.20.2.
Confirmed in 23w16a.
Yes, I believe it is very related to that bug report/feature. However, if you do the setup as in the picture "Spreads2", the stone with the carpet on it does end up converting to sculk. This doesn't make sense if the stone has to have air above it in order for the sculk to spread normally. For some reason, this particular setup, with the mobs dying on a block directly touching a sculk block, causes this rule to be ignored. Hence the inconsistency.
Confirmed in 23w14a.
I believe the video that was added to my bug report demonstrates that sculk blocks cannot spread unless they have an open face. I am not sure if this is directly related to the bug or not, but different results from the video occur when the sculk block has an open face on the bottom of the block (as in the pictures). The discrepancy between how carpeted stone and carpeted sculk (or carpeted stone adjacent to a sculk block) react occurs when these blocks have an open side.
Confirmed in 1.19.4 pre releases 3 and 4.
Can confirm, in 1.19 pre release 2 mobs don't spawn on mangrove roots. However, in pre release 3 and above they will.
Can confirm, in 1.19 pre release 2 mobs don't spawn on mangrove roots. However, in pre release 3 and above they will.
Confirmed in 25w34b.