Hextech Bug

Basically what would happen is that I would create a game lobby, ranked or not tried both, and I would enter que. I would check other tabs like the store and my profile while I wait but when I click on the Hextech crafting tab my Client would just close itself out majority of the time. It would remove itself from my dock of my laptop and acted if I completely closed out the client it, which I didn't. I would click back onto the icon to restart it and It would say I have another session running. I don't know if its a real bug or me just not noticing something obvious.

Thanks