Title says all. Tested with 1.16.5-r419 with a partially full pulse mana spreader with no attached mana pool. This probably shouldn't happen as there are uses in having a returning mana burst. Most namely not needing a return spreader for activation/deactivation of various drums, the hovering hourglass and anything else affected when a mana burst hits the block(s).

The issue is bursts have a hardcoded override to never collide with their originating spreader after fired. This was a hack to prevent bursts from colliding with the spreader while being spawned, but the hack can be refined to not collide as it's exiting and then start colliding after it's left once.

Looks to be fixed on the Fabric branch in 1db14e8

fixed in 1.17
keeping it out of 1.16 just in case someone was somehow relying on these properties