Originally posted by SmachingCube:

It was working for me. But now, my F5 does exactly nothing in game.

Important Update! To activate the console, you will now need to set it as a launch option in Steam. By default, the command console is now locked.

Here's how to activate the console:

Right-click Valheim in your Steam library
Select Properties
In the General tab, look for the Launch Options field
In it, type -console
Close the General tab