https://sh.itjust.works/post/24577129

In a “NoSafetySmokingFirst”, the text reads correctly left to right, but visual cues (like colouration, vertical proximity, or horizontal separation) lead you to try to read it top to bottom.

This is similar to, but distinct from, the more widely known “DontDeadOpenInside” format. In that case, the text reads correctly top to bottom, but visual cues (like colouration, horizontal proximity, or vertical separation) lead you to try to read it left to right.

Examples in the pinned post.

So no safety smoking first is text that meant to be left to right but is instead read too to bottom

Don’t dead open inside is the opposite, meant to be be read top to bottom but instead left to right

So basically No | safety Smoking| first

Is read as

no safety —————- Smoking first