As seen in the pictures, firework particles are infinite under the player. I found this bug because I was messing around w/ tnt, had a bunch of lag, then flew with elytra. Tried to power with firework, did not work, stopped flying and hung in midair, and after a few moments, the particles showed up. They disappeared immediately after the explosions stopped.
MC-166215
Firework particles appear indefinitely during explosions
Resolved
Awaiting Response
0
Maybe this was because of explosions lagging the game, causing the particles to be delayed