Fix: Cannot read property ‘extend’ of undefined

[riungemaina]

Fixes #56.

[Pierstoval]

I have used a hack in my project (in this commit which is "a bit" similar, but it's a hack, not a fix.

The main problem is that dayjs is undefined after being imported, and I have no idea why 😕

However, this seems like a common issue in dayjs.

[riungemaina]

Oh, I'll look for a fix and if that's available, I can add it and make a PR.

[Its-Just-Nans]

Hello,

A possible solution here : #61