Lets be honest, we all want little fire fly lanterns. Nice decor block, new light source, particle emitter perhaps. The main issue? Fire flies, infinite buggers, and this as far as I know is the main reason admins hold back implmentation of Firefly jars.

My Solution? The new interaction display entity!

How it would work, is the player would right click with a new jar item when in biomes with fire flies. Doing this would interact with a display entity inside the chunk.

This would set a counter stored by the chunk display entity lower. When that value is zero, fire flies would no longer show up or be collectable in that chunk, and the entity would be removed for a time until the entity is respawned like normal spawn mechanics for passives, letting fireflies still be particles, yet like normal entities for collection and collection limits. These interaction entities would obviously only load when a player is in said chunk, in order to save data, and would only stay if the value was less than the standard amount. The mark of these entities to know to spawn being the presence of the particles. If lag was still an issue, it could be made so you have to empty a chunk to fill a fire fly jar.

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In addition, in order to limit the jar more, which is a worry along with the fireflies being an infinite resource, the jar itself could be either a arceology relic, or have an expensive/time consuming recipe.

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with new vanilla firefly bushes you could just… surround a bush would glass…