Waiting for lock on pidfile .jlassetregistry.lock

A module of mine is using several other modules/packages.
When I load my module @everywhere I get infos about “waiting for lock on pidfile .jlassetregistry.lock”. Can someone help me understand this?
Can I find out which package is causing this?
At least once I ran into an error because of this.
Is there any way I can avoid this info (e.g. should I schedule the import on the different workers such that it does not happen in parallel?)

by opening the json file .jlassetregistry.json in my home folder I could see that PlotyJS and WebIO were causing this (or at least these were the relevant packages). I was able to ‘outsource’ these packages/dependencies to a separate package (which I do not need to load on all workers)