[Suggestion] Saving Chatlogs from players who unfrend you

Since League of ~~leavers~~ Legends private message threads are deleted upon unfriending/blocking other person. it would be nice that you could still see the chatlogs so that you could report those people who just add you after the game and say really mean stuff about you via PM messages. Since PM's are private riot does not have access to your chatlogs and you cant report this kind of behaviour. Could we get some sort of chatlogs that you can see after person unfrend or block you so you could send screenshots to riot for this kind of behaviour?
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