Thanks for playing my game
The bug is normally either due to particles or shaders taking in time to load and get buffered by the browser as the projectile spawns, there are a few solutions but i didn't really got to implementing them. One of them is spawning the projectiles during a loading screen under an overlay that still makes browser recognize them, so they get buffered and are ready to use when you actually use them, but tbh I actually forgot this was a problem lol.
Also thanks for the feedback on camera shake