My issue may be difficult to understand so I tried to include a video of what is happening but it doesn't let me. I narrowed it down to being an issue with this mod because it only happens when it's in my game. When you place a block and then break it it doesn't stack with ones that are already in your inventory.

Example: I have a stack of 64 Moss in my hot bar I place 3 and break those 3. When I pick those up after breaking they do not return to the stack of now 61 but rather make a new stack of their own.

Log: https://mclo.gs/KZll0x2 or https://pastebin.com/MYsAdF8n (not sure which is better but i included both the copied from my modrinth app and a pastebin)