Cannot hit stuff from a minecart because the minecart's hitbox extends beyond its apparent top.
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[media]
Confirmed. This has been around forever.
has been around forever? if forever is since 1.5 or 1.5.1, then yes. or it has been gotten worse since 1.5.1 and was unnoticeable b4. since 1.5.1 it takes 3-20 seconds to completely "sit down" in a minecart. only then you are able to press buttons etc.