Something about runtime errors.

code/modules/mob/living/simple_animal/parrot.dm

@@ -332,8 +332,8 @@
 		speak_chance *= 1.27 // 20 crackers to go from 1% to 100%
 		speech_shuffle_rate += 10
 		to_chat(user, "<span class='notice'>[src] eagerly devours the cracker.</span>")
-	..()
-	return
+		return // the cracker was deleted
+	return ..()
 
 //Bullets
 /mob/living/simple_animal/parrot/bullet_act(obj/item/projectile/Proj)

code/modules/power/singularity/particle_accelerator/particle.dm

@@ -59,7 +59,12 @@
 
 /obj/effect/accelerated_particle/proc/move()
 	if(!step(src,dir))
-		forceMove(get_step(src,dir))
+		var/turf/T = get_step(src,dir)
+		if(T)
+			forceMove(T)
+		else
+			qdel(src)
+			return
 	movement_range--
 	if(movement_range == 0)
 		qdel(src)