The idiom "of course" is used to express that something is obvious or expected. It can be used to indicate agreement, approval, or understanding.

The idiom "follow by" means to be close behind or to follow something immediately after. It can also mean to occur or happen at the same time as something else.

The idiom "cut somebody some slack" means to give someone a break, allow them some leeway or flexibility, or grant them forgiveness for an error or mistake. It is often used when someone has made a blunder or misstepped and needs some understanding and acceptance from others.

The idiom "the devil is in the detail" means that when trying to solve a problem or achieve something, it's important to pay close attention to all the small details.

The idiom "lightning fast" is used to describe something that happens or moves very quickly, almost instantly. The figurative or metaphorical meaning of this idiom is that the action or speed being described is amazingly fast and speedy, beyond what is expected or normal.