Glass panes become opaque when near them (<20 blocks), when you move out of that range they function normally again.
Environment
Vanilla server on 14w03a, when close to a regular glass pane (<20 blocks)
Glass panes become opaque when near them (<20 blocks), when you move out of that range they function normally again.
Vanilla server on 14w03a, when close to a regular glass pane (<20 blocks)
Duplicate of MC-44990