I don't know if it is linked:
https://bugs.mojang.com/browse/MC-165595
But with spigot, all my lasers are only bubbles in the world.
Some of my customers reported me that in some worlds that's fine.
So I decided to switch to paper spigot, and this is working, lasers are always displayed.
My code:
https://paste.md-5.net/huremodohe.java