I need to do a debug thing, how do I type it in the game? elsewhere I have read that I have to press '~' but it does nothjing

The actual character you need to produce is grave accent (a.k.a. backtick), not tilde. All the guides say to press the tilde key because that is the key that produces the grave accent character on a US keyboard layout (the shift character for that key is tilde, hence the name).

In order to produce a grave accent character on my keyboard with Swedish keyboard, I need to hold down the shift key and press the key for acute accent (located to the left of backspace), and then press space (because both accent marks are treated as combining characters).

In the common UK layout, I think the grave accent character is produced by pressing the key above the tab key (to the left of the 1 key). This is actually the same key as in the US layout, except that the UK layout uses a different key for the tilde character.

Also, some variants of the US and UK layouts treat grave accent as a combining character, thus requiring you to follow with spacebar to produce a stand-alone character.

wow brilliant response, thank you. ;)