Anyone knows why my infused TNT cannon explodes?

[gleaming glade]

So I infused my TNT cannon and hinged it to an obsidian rail and tried to align it parallel to the ground. Although my TNT cannon was waterlogged so that I won't expect it to explode when dispensers throw the TNTs, my infused TNT cannon somehow managed to explode. Anyone knows why this happened? I don't think the TNTs passed the waterlog boundaries when they were exploded.

[shrewd temple]

I think what happened is that the TNT got transformed to the world

at which point it didn't think it was in water

it exploded

but then that explosion was modifed to explode the ship aswell

basically, this is probably a bug