A javascript file containing import statements referencing Firebase browser modules embedded in an HTML file needs to be declared as type="module". But after conversion to ES6 modules, this qualifier seems to be optional.
Is a "bundled" javascript file no longer regarded as a module? It certainly still behaves like a module, at least in the sense that a Javascript function in your bundled file remains unavailable to the DOM (eg, an "onclick" reference to a bundled function won't work).
Examples of tags in Google documents seem to confirm the pattern - scripts using browser modules should be declared type="module", bundled scripts should be left unqualified. But what exactly is going on here?
Advice would be much appreciated
Yes, before you build an app, i.e. before you do npm run build, remove type="module" from all the script tags.
What happens under the hood is that the bundler puts all the code from your .js files into one big file. You can find that file inside you dist folder.
If you're using Webpack or Parcel or any other bundler, they convert JS from ES6+ to ES5, and ES5 does not support import statements, that is why it puts all the js code into one big file.