Merge branch 'master' into upstream-merge-37476

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code/modules/projectiles/guns/misc/beam_rifle.dm

@@ -436,7 +436,7 @@
 
 /obj/item/projectile/beam/beam_rifle
 	name = "particle beam"
-	icon = ""
+	icon = null
 	hitsound = 'sound/effects/explosion3.ogg'
 	damage = 0				//Handled manually.
 	damage_type = BURN