Proposal: move browser specific settings to browser_specific_settings

[carlosjeurissen]

Several manifest properties are browser specific like minimum_chrome_version and minimum_opera_version. To align with Safari, Firefox and edgeHTML, these should be defined in browser_specific_settings.

"browser_specific_settings": {
  "chromium": {
    "strict_min_version": "14",
    "strict_max_version": "20",
    "key": "some key",
    "container": "some container"
  },
  "opera": {
    "strict_min_version": "14",
    "strict_max_version": "20"
  }
}

Some of these can be specified as being the same for each platform. Like strict_min_version and strict_max_version, while some are unique for a specific platform like key and container are for Chromium.

[xeenon]

Safari already implements support for:

"browser_specific_settings": {
  "safari": {
    "strict_min_version": "14",
    "strict_max_version": "15",
  }
}

I believe Firefox does as well for the firefox key.

[Rob--W]

Relevant note: Chrome is open to support for browser_specific_settings.strict_min_version, but it is not a priority to implement. This was discussed during TPAC last yet, with meeting notes captured at:

webextensions/_minutes/2024-09-24-wecg-tpac.md

Lines 431 to 437 in 233d77a

	* [Issue 115](https://github.com/w3c/webextensions/issues/115): Proposal: move browser specific settings to browser_specific_settings
	* [rob] Are you neutral or opposed towards adding chrome to browser_specific_settings?
	* [devlin] What is put there?
	* [rob] E.g. putting strict_min_version.
	* [timothy] We use it in that way too.
	* [rob] Chrome could then add a browser_specific_settings.chrome.strict_min_version key with the semantics of minimum_chrome_version.
	* [devlin] No objections, would not be a priority to implement.