Custom File Match

[fredboyle]

Attempting to use a custom file matching pattern to only process .mdx files and ignore .js but not having any luck.

I've added:
export const files = require.context('.', true, /\.mdx$/, 'lazy')

To the root level index.mdx file but it is still attempting to process .js files.

What might I be doing incorrectly?

Thanks for your help.