Yesterday night I was playing a 3+0 tournament game when the site updated. The game was quite equal and time was running low for both players. Then a site update happened, I got disconnected and lost the game because of being unable to reconnect.
I think Lichess must work something around this problem. Suggestion: suspend the game when a site update happens and give a chance to the disconnected player to reconnect instead of forfeiting. Whatever happens with this problem, something has to be done to prevent players from losing games that way.