@Okta, this is my mail to them:

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Good morning XXXXX, I think it will be nice if we will have an option for friendly games if we alow them or no, I mean you can set if they can challange you to friendly games or no. Because I have friends who are on top close to me and before some hard games they duel me to lose in League )
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This is a part from answer (I'm not allowed to copy-paste all):

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We are trying to find some way to solve this problem!
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