Affects Version/s: Minecraft 17w45b, Minecraft 17w46a, Minecraft 17w47a, Minecraft 17w47b, Minecraft 17w48a
Fix Version/s: None
If you run an execute command that runs through multiple entities, and it has a condition, all executing entities must have the condition.
/execute as @e[type=arrow] at @s if block ~ ~ ~ minecraft:glass_pane run setblock ~ ~ ~ minecraft:air
will only have the arrows set the block relative to themselves to air IF all arrows are in a glass pane block.