The error message is cryptic

[mytskine]

I ran a command web-ext sign ... and got the following error message:

WebExtError: Submission failed (2): Bad Request
{
  "version": {
    "license": [
      "This field, or custom_license, is required for listed versions."
    ]
  }
}
    at file:///.../web-ext@9.3.0/node_modules/web-ext/lib/cmd/sign.js:101:13

What am I supposed to understand?

• Is it about a file in my source code? Which one?
• Is it about a parameter of web-ext sign? But I couldn't find anything related.
• Is it about a field "licence" under "version"? Or is "version" just something internal to the API or web-ext?

My addon source dir has a "LICENSE" file.
There is also a "manifest.json" v3 file, with "version": "1.0.0".
I tried adding a "license": "GPL-3.0-or-later", line. I read all of the MDN doc and Mozilla doc I could find. There was a discussion about this JSON error in an Github-actions context where the solution was to change the API call. One hour after, I still have no idea how to fix this.

Could you please turn this error message into something a human can parse?

[rpl]

We have just touched base about this issue in our triage meting and we agreed that web-ext should be linking the doc page for the metadata endpoint when the request that web-ext is internally submitting when it is receiving an error from the server.

The doc page to link:

• https://mozilla.github.io/addons-server/topics/api/addons.html#version-create
• https://extensionworkshop.com/documentation/develop/getting-started-with-web-ext/#:~:text=Create%20your%20metadata%20file

Relevant logic on the server side: https://github.com/mozilla/addons-server/blob/8a1f6e9df9f29db2c3a48e4983e31219ed739deb/src/olympia/addons/validators.py#L45-L70

[Rob--W]

We should also improve the documentation. The docs offer an example that includes a license, but does not emphasize that it is required: https://extensionworkshop.com/documentation/develop/getting-started-with-web-ext/#sign-and-submit-for-publication