JavaScript I'm trying to make a web extension that reverts youtube to an old layout, but i barely know anything about js or css

[dachshund999]

so im trying to make a web extension that changes the current youtube layout to an old version that i plan on completely writing from scratch im trying to change the background but i think im doing it wrong

this is my manifest script

{
    "manifest_version": 3,
    "name": "CosmicPandoReloaded",
    "description": "Makes youtube look like an accurate version of Cosmic Panda",
    "version": "1.0",
    "icons": {
        "16": "/images/icons/16.png",
        "48": "/images/icons/48.png",
        "128": "/images/icons/128.png"
    },
    "content_scripts": [
        {
            "matches": ["*://*.youtube.com/*"],
        "js": ["fronts/main.js"],
        "run_at": "document_start"
        }
    ],

    "permissions": [
        "activeTab"
    ]
}

and this is my main script

function changeYouTubeBackground() {
    document.body.style.backgroundImage = "url('https://web.archive.org/web/20120717011147im_/http://s.ytimg.com/yt/imgbin/www-refreshbg-vflC3wnbM.png')";
}
  changeYouTubeBackground()

idk what i did wrong any help would be great

 

[Johna]

You're trying to change the background image of the body element before it even exists by setting run_at to document_start in your manifest.json.

Try setting it to document_end.

 

[dachshund999]

You're trying to change the background image of the body element before it even exists by setting run_at to document_start in your manifest.json.

Try setting it to document_end.

tried that, but sadly didn't work, i did hear some where that using

"host_permissions": ["*://*.youtube.com/*", "https://www.youtube.com/*", "https://*.googlevideo.com/*"]

could get it to work but that also didn't help

 

[Johna]

Are you sure you're the js is in the right place?
Have you tried writing a console.log() in the script and seeing if it prints it in the console? that's if an extension can even print to the console, idk, it's been a while since i made an extension.

Maybe you have to add !important to the CSS, or there's another element in front of the body with a background colour covering the body's bg colour?

 

[dachshund999]

Are you sure you're the js is in the right place?
Have you tried writing a console.log() in the script and seeing if it prints it in the console? that's if an extension can even print to the console, idk, it's been a while since i made an extension.

Maybe you have to add !important to the CSS, or there's another element in front of the body with a background colour covering the body's bg colour?

yeah, its all in the right place, just doesn't seem to load