Can't equip TF2 items

[mtmkls]

In the robot enrichment I can only see the one hat I got for completing the story. How do I equip the Mann co. hat for example?

BTW neither the store nor trading works.

[mtmkls]

Now I tried the game with Wine, and it's the same.

[Blayer98]

The Store was shut down in 2015 apparently, and trading was never implemented.

Apparently, I've heard that Synced hats are no longer supported which is why you can't equip the Mann Co. Hat.