Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
Speakers have a "Show alert" checkbox. The mod shouldn't show speakers that have it unchecked since they are presumably either disabled or are used purely for sounds.
I submitted a PR on Github:
https://github.com/NoUserToSeeMoveAlong/factorio-alerts/pull/1
I have released Version 1.3.1 - Thank you!
