You can't reconnect to a match if you lose internet connection and restart the Client

Instead you'll be faced with a lobby that states "Players are not ready". There's no reconnect button.

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My Internet had gone out in the middle of a winning match. I called, got it fixed, restarted league, and wanted to get back in the game so my team wouldn't lose. Instead, the League Client did not allow me to reconnect (the game was ongoing). Not only did I lose points (and I'm sure honor, as well as receive multiple reports for "afking"), but my teammates, who should've won the game, also received a loss. This isn't fair and this isn't the first time it's happened, nor the first time I've notified Riot Games about it.

Please fix this bug. It's a pretty bad one.