add a new front end question

[anubhavadarsh]

add a question about variable fonts and a link to mdn page explaining the same.

[anubhavadarsh]

Hi there! Thanks for your contribution. I love this question and I'll read your source shortly. I actually don't know the answer for this one.

Would you mind adjusting your line to have a trailing comma after the end quote? This will make it easier for the next person to add their question. Like this: 'question here', # source

thank you, I made a new commit with the trailing comma.