remove fetch polyfill

[adamkasprowicz]

No description provided.

[developit]

Hiya - I've been tracking down a large bundle size problem and noticed a number of copies of whatwg-fetch, of which Keen's embedded copy was one. Do you have a timeline on when this might be possible to implement?

FWIW another option you may want to consider is unfetch (disclaimer: I am the author). It looks like Keen only uses basic fetch functionality, in which case just replacing whatwg-fetch with unfetch would trim somewhere between 3 and 10kb off your library size without worrying about browser support.

[stof]

including unfetch as a polyfill would be a bad news: it would also affect projects wanting to use more complex fetch features (unless the feature detection of these projects accounts for the partial implementation of unfetch)