Most furstrating bug :
console.lof()
yup! lof not log

Console wants some lof to

No #s needed in tags btw

Made me lof, right out loud

If it's a common typo perhaps alias it console.lof = console.log.

I am grateful for TypeScript. This is exactly the type of errors that disappears with statically typed language. I have a vivid memories of dealing with this stuff in other project with JS - undefined magically bubbling through countless layers, including several async ones...