What are the 3 red squares?

Packet Loss (red squares)

Packet loss is represented by two squares with a dotted square between them, all arranged diagonally.

This means your computer is failing to send information or receive it from the Apex server. If your character is freezing for a while then suddenly teleporting, or if you’re shooting someone and they’re not receiving damage, that might mean you’re experiencing packet loss and that the server never received information from your end.

You can also interpret it as an extreme latency. If in high latency it takes longer for information to be transferred, in package loss, some information is never transferred. And just like with latency, this issue is commonly linked to your own connection.