You're micro observing stuff, again, which is not bad in itself. If you have a cap that leaks, get rid of it. No reason to sort it out.
End of story.
I wouldnt say im micro observing this but i am observing it yes.
I bought a cap that looks like any other q/r cap but with a full tank it weaps out the breather but i think i sussed it.
Some of the dear ones are identical to mine but they have a tiny tube from the breather hole that you poke down into the tank breather hole so any leakage doesnt spill over the front of the tank.
Im an engineer so if theres a problem a look for the solution and try to fix it.