Pasted solution doesn't work - even after reset

Tell us what’s happening:
This is a straight forward and simple lesson. But I got a strange error in the console window: ‘ReferenceError: exports is not defined’

I though, “Ugh, I’m not too proud”. And I checked the solution on the hint page. After I pasted the solution, the error was still there. I reset the page and still no joy.

Could the lesson be broken? I could try to reset the browser (close and reopen) next. After that I could try to clear the cache.
What do you think? This is the first time it has happened that a solution I copied and pasted doesn’t satisfy the test.

Your code so far

export const uppercaseString = (string) => {
return string.toUpperCase();

export const lowercaseString = (string) => {
return string.toLowerCase()

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:76.0) Gecko/20100101 Firefox/76.0.

Challenge: Use export to Share a Code Block

Link to the challenge:

So the error is still there, but it allows me to pass the test.

Not quite sure but it may occur because most of the challenges on freeCodeCamp use the (ES5).