WebExtension在Firefox中无提示失败，但在Chrome中没有失败

Question

I'm making a WebExtension for Chrome and Firefox that adds more information to GitHub. It's supposed to be faster than existing extensions.

I have my manifest set up like Mozilla's documentation recommends.

{
    "manifest_version": 2,
    "name": "GitHub Extended",
    "version": "0.0.1",
    "description": "Adds information to GitHub normally accessible only by the API.",
    "permissions": [
        "https://github.com/*"
    ],
    "content_scripts": [
        {
            "all_frames": true,
            "run_at": "document_start",
            "matches": [
                "https://github.com/*"
            ],
            "js": [
                "source/github.js",
                "source/repository.js"
            ]
        }
    ]
}

When the page is loaded, the content scripts are injected. The file github.js is a light wrapper around GitHub's API, and repository.js is the code to modfy the DOM of the main repository root page.

The most important code in there is this the preloader, which makes an API request while the page is loading and waits for both events to complete before adding to the DOM.

While this current code works fine in Chrome, in Firefox it simply does nothing. I tried testing it by putting console.log("I'm loaded!"); in repository.js . Nothing is printed. Why is this code not working in Firefox?

function beginPreload() {
    console.log("Test from preload scope!");

    let urlMatch = window.location.pathname.match(/\/([\w-]+)\/([\w-]+)/);
    console.log(urlMatch);

    Promise.all([
        getSortedReleases(urlMatch[1], urlMatch[2]),
        documentReady()
    ]).then((values) => {
        let releaseJson = values[0];

        let actionsEl = document.getElementsByClassName("pagehead-actions")[0];
        let dlCount = 0;

        for (release of releaseJson)
            for (asset of release.assets)
                dlCount += asset.download_count;

        let buttonEl = createDownloadButton(
            releaseJson[0].html_url,
            window.location.pathname + "/releases",
            formatNum(dlCount)
        );

        actionsEl.appendChild(buttonEl);
    });
}

beginPreload();
console.log("Test from global scope!");

Answer 1

This was the solution.

"permissions": [
    "https://api.github.com/*"
]

All that needed to happen was add permission for the extension to use GitHub's API. AFAIK, this is only required for content scripts using XHR.

Answer 2

You need to go step by step and first ask yourself if script is really injected in the FF github page: remove everything thing from your contentScript, reload extension and check your FF console. If you see the log then start adding code progressively until it breaks, if not you have a problem with your build content.