Today I learned that Markdown code fences can use any number of backticks (`) or tildes (~) as long as the number is at least three. The closing fence must have at least as many characters as the opening one.
This is especially handy for nesting code blocks that contain backticks, such as when documenting Markdown itself.
For example, to include triple backticks in a code block, you can use four tildes:
````
This is a code block with ```
````Which renders as:
This is a code block with ```