Minecraft wiki entry for Development_versions, associated text: Ruined portals in nether now use blackstone.
Fire charges can now be found in ruined portal chests.
Tweaked ruined portal loot tables - changed number of rolls to match Java.
Updated bastion loot tables (MCPE-69005, MCPE-68986).
Magma cube spawners now generate inside bastions (MCPE-69424).
Walls in generated structures now form the proper connections (MCPE-66369).