Netlify deploy failing

[zzrez]

Hi, I clicked the green Deploy to Netlify button, and it failed. In the Netlify control panel I then clicked to try Deploy again, with cache removal. Same result. In both cases this was the error message Netlify gave:-
5:23:23 PM: error "gatsby-plugin-netlify-cms" threw an error while running the onCreateWebpackConfig lifecycle:
5:23:23 PM: Module not found: Error: Can't resolve 'fs' in '/opt/build/repo/node_modules/@babel/core/lib/transformation'
5:23:23 PM: ModuleNotFoundError: Module not found: Error: Can't resolve 'fs' in '/opt/buil d/repo/node_modules/@babel/core/lib/transformation'
A pity as I wanted to study the NetlifyCMS settings.

[l3aconator]

This is a hack but the issue is MDX run time, and you need to set node: { fs: 'empty' } in gatsby-confg.js. See here:

mdx-js/mdx#913
webpack-contrib/css-loader#447 (comment)
gatsbyjs/gatsby#10326 (comment) <- this is the issue, but you need to modify the plugins config NOT your local config, they are separate. here is the hack below:

{
      resolve: `gatsby-plugin-netlify-cms`,
      options: {
        modulePath: `${__dirname}/src/cms/cms.js`, // for custom preview in the Netlify CMS
        customizeWebpackConfig: (config) => (config.node.fs = 'empty'),
      },
    }