When source water is placed next to a corner of dry glass panes, the panes will become waterlogged and start flooding the other side.
I can only hope this isn't the intended behavior, since there's no reason a wall made of glass panes shouldn't be water-tight.
Is there a way to request this to be re-opened? The resolution to the issue this is marked as a duplicate of does not apply to the situation I'm describing. The other issue was marked as "Invalid" apparently because it was believed that the person reporting the issue just put water in the glass pane, which isn't what I did. Placing water outside the glass panes surrounding (not in the same space as!) the corner causes the inside to become flooded (or vice versa, as technically shown), which is extremely poor and irritating behavior.