[09:28:03] [main/ERROR]: Couldn't load item tag minecraft:walls as it is missing following references: addendum:midori_brick_wall (from Addendum)
[09:28:03] [main/ERROR]: Couldn't load item tag minecraft:stairs as it is missing following references: addendum:midori_brick_stairs (from Addendum)
[09:28:03] [main/ERROR]: Couldn't load item tag minecraft:slabs as it is missing following references: addendum:midori_brick_slab (from Addendum)
[09:28:03] [main/WARN]: Failed to load datapacks, can't proceed with server load
java.util.concurrent.ExecutionException: java.lang.IllegalStateException: Missing required tags: minecraft:block:minecraft:slabs,minecraft:block:minecraft:stairs,minecraft:block:minecraft:walls,minecraft:item:minecraft:slabs,minecraft:item:minecraft:stairs,minecraft:item:minecraft:walls

@RDKRACZ everything should work now just tell me if anything is wrong

Ok so I have tested everything and I'm making a release on curseforge, if the issue continues then just leave a comment