Someone changed my profile picture?

[General_Torpedo]

So some days ago I logged in to steam to encounter that my pfp was a QR with Chinese (I think) letters on it.

I also saw that apparently I had send friend request to some rather suspicious accounts (One with a Chinese name, 4 others with just random numbers), as well as having sell almost all of my inventory stuff I had (I didn't had much really, didn't even made one dollar), also, I gave at least two community badges to some who I don't remember the name of, but I am pretty sure that it was a pretty suspicious account.
I already scanned for malware with malwarebytes both my laptop and phone, I've changed my Passwords of both my steam and mail, and deauthorized all other devices.
What else can I do?
Other than that, nothing else has happened as of now, I changed back my pfp and that is pretty much all.

[Steven]

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