Missing documentation on prefetchPathname

[wahidshafique]

Preliminary Checks

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Summary

Apparently this method was introduced here #8122 (comment) but I cannot find the relevant details. I'd like to prefetch a path programatically.

The api was exposed publicly here 7173f96

Steps to Resolve this Issue

Outline the steps involved to prefetch a path programatically in Gatsby's official docs. A suggested solution and where it can live is here #13985 (comment)