The Tavern

Not sure if this is a bug or if so if it's already known, or there's something I'm missing...

Playing webtiles 0.23 as a GnSk of Oka
Whenever I try to target a monster with a thrown projectile with Portal Projectile active, if an ally is standing next to the target, I get the warning that targeting my ally will cause penance.
But I'm not targeting the ally, but a hostile monster on the other side of it - somehow the game thinks I am targeting the ally.
This does not happen if there is a clear gap between my ally and the hostile monster.
I have not actually tried going ahead and throwing the projectile in case it does somehow hit my ally.

When reporting issues, please use the bug tracker, and include the version string from ?/V and as much information as possible. In this case, what you’re throwing; I recently added a friendly fire check for exploding projectiles, if you’re using them then there’s no bug. If you aren’t, there’s a problem.

Bug report submitted here:

https://crawl.develz.org/mantis/view.php?id=11858