Confirmed to not be happening in 1.16.5. Issue is confirmed to be starting with 21w03a. All future versions are likely affected.
[media][media]When a zombie is in a minecart that drives under bottom half slabs, it starts to burn. This does not happen if it is inside of a full block or underneath top half slabs. This does not seem like an intentional change and might be a side effect of some other changes made. If intentional, please mark as "works as intended"
Issue still persistent in 1.19, also affects bottom half stairs.
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