Incorrect end portal(structure blocks) texture

when placing down the structure blocks of the end portal, one side of each block always appears to show a weird blue texture with an eye of ender near the middle. this may possibly be the "front" of the block, but that is supposed to be rendered invisible, I think. (the end portal didn't activate when it was supposed to, leading me to further question this.)

this is not a necessary-fix bug, but some confirmation on what it is would be helpful.