When I was In A StrongHold, I found the end portal, I walked up and the eye of enders already inside it by the silverfish spawner, but i saw through the sides!
Linked issues
duplicates 1
Comments 4

I did not understand the bug. Some random slots of the portal, but not all, may have eyes of the ender placed when you find the stronghold. That is intended.
And seeing through the sides of portal blocks has been fixed in 1.4.3 IIRC.

Duplicate of MC-74
Can you post a screenshot?