If you make other people uncomfortable on our forums, especially by mistake, apologize, or say nothing.
So if you make someone uncomfortable without even realising why, you have to apologise. Especially if you've no idea what you've done wrong.
Avoid subtle -isms. These are small things that make others feel uncomfortable, things that we all sometimes do by mistake. For example, saying "It's so easy my grandmother could do it" is a subtle -ism.
Which is in no way patronising. At all. Not one little bit.
And the best bit
Don’t argue about civility on public channels. Don’t defend yourself, don’t defend others,
So if someone's uncivil to you, you're not allowed to defend yourself, and if someone else has people being uncivil to them, you're not allowed to defend them either. Classic.
No wonder the admin quit, is it?