texture.hasAlpha leave a border line

Hi,guys.I got a problem with texture.hasAlpha.What below is the picture I use as the texture, it should be a red piece.

However,it turn out like this.There is a borderline.I tried editting the picture,which doesn’t work.

Anybody knows about this problem?

Here’s the PG.
Plane Examples | Babylon.js Playground (babylonjs.com)


Thanks a lot