Is increased rarity of items by killjoy unique gloves?

Killjoy Linen Wraps has modifier 'On-kill effects happen twice', does this apply to increased rarity of items modifiers?

Its difficult to test it, so looking for a response from GGG if possible.

I've also been googling about this unique, but for different reason. I'm wondering if the herald effects which occur when an enemy dies under certain conditions will proc twice with these gloves. i.e. if I use herald of ice, will the enemy explode twice? its hard to tell in game.

no

wording is the key to understand poe

effect on kill so the mob dies only once

effect on kill is for examnple (don t know if exist)
gain phase run for 5s when you kill an enemy
you will have phase run for 10s

effect on kill affect only the wording on the item

%armor is the armor of the object, not global armor

and so on ...