Plugin ESM support

[1Code-JS]

Check for existing issues

• Completed

Describe the feature

• Find workarounds to correct Content-Type to text/javascript
• Open a pull request

To allow plugins (with "type": "module"* in their plugin.json) to be ran as ESM without any transpilation steps. Currently, they are being loaded as a classic synchronous script (in a <script> element without type="module"), as seen in src/lib/loadPlugin.js.

*May be subject to change

If applicable, add mockups / screenshots to help present your vision of the feature

(Code shown may be subject to change)

[1Code-JS]

There is one issue: JS files served from /__cdvfile_files-external__ return Content-Type application/javascript instead of the required text/javascript, thus resulting in this error when being parsed and ran as ESM, whether by type="module", import statement, or import().

Blob URLs?

Relative import URLs (.//../) will not work. Either plugin devs themselves must use absolute paths or transpilers must resolve these paths. For the latter, some configuration is required to inject /__cdvfile_files-external__/plugins/insert.plugin.id/ prefix onto absolute paths.