[phoenixframework/phoenix#4662] There is a problem that phoenix.js is shipped in a phoenix.esm.js and phoenix.cjs.js formats. When using Next.js with esmExternals: true the system tries to load the cjs instead of the esm.
The solution is to just change the file name from phoenix.esm.js -> phoenix.mjs.
Because it modifies the package.json this can't be done in a local project patch. So I'm just snap shotting 1.6.6 and making the change - with the hope that this will setting down in the future
Copyright (c) 2014, Chris McCord.
Phoenix source code is licensed under the MIT License.