its not a bug
Friends tab doesnt check your actual friendlist, neither it knows whether the games were played in party or in solo q, cz it doesnt appear in steam API, afaik. it just includes all the people that were on your team 3 or more times.
კომენტარის დასაწერად გაიარეთ ავტორიზაცია.
These people are not on my friendlist why are they showing that they played with me?