Certain mobs apply a "disarm" effect that removes your weapon temporarily. This also disables any skills that require the weapon, so those will all be grayed out whenever you get hit by a disarm.
However, I have been seeing a bug lately, where my weapon fails to reappear at the end of the disarm. My skills all come back, and my character goes through the attack animations normally, but the model of the weapon remains invisible. For me, this has been happening in the Lone-Lands, though also with Orcs. (I think there are several varieties of Orc capable of inflicting the disarm debuff.)
I believe, however, that I have also had issues with having my skills return, but not having a weapon to use them with. I will have to keep an eye out for that one later on.
I have experienced similar issues with missing models (not disarmed)
Usually it happends to me if I get attacked during or shortly after harvesting a node.
The "missing weapon" happens on my warden when I switch out a weapon in combat. Nothing to do with being disarmed; it doesn't happen all the time; sometimes the weapon model will come back if I switch again, sometimes it doesn't. But the glow effect of the LI is still there. Can be disconcerting at times.
As far as farming nodes, I've found if I start an attack immediately after getting the node, without stepping away from it, no matter which character I'm on, 100% of the time there will be no weapon. Take one step away, and all is fine.
To many people, free will is a license to rebel not against what is unjust or hard in life but against what is best for them and true.
However, I have been seeing a bug lately, where my weapon fails to reappear at the end of the disarm. My skills all come back, and my character goes through the attack animations normally, but the model of the weapon remains invisible. For me, this has been happening in the Lone-Lands, though also with Orcs. (I think there are several varieties of Orc capable of inflicting the disarm debuff.)
same with goblins in the Midgewater marshes today.