A configuration for the Redirector Firefox Extension https://einaregilsson.com/redirector (credits to Ploum for the idea)

redirector.json

{
    "createdBy": "Redirector v3.5.3",
    "createdAt": "2023-12-16T22:17:12.106Z",
    "redirects": [
        {
            "description": "Youtube",
            "exampleUrl": "https://youtube.com/truc",
            "exampleResult": "https://piped.kavin.rocks/truc",
            "error": null,
            "includePattern": "https://*youtube.com/*",
            "excludePattern": "",
            "patternDesc": "",
            "redirectUrl": "https://piped.kavin.rocks/$2",
            "patternType": "W",
            "processMatches": "noProcessing",
            "disabled": false,
            "grouped": false,
            "appliesTo": [
                "main_frame"
            ]
        },
        {
            "description": "Reddit",
            "exampleUrl": "https://reddit.com/truc",
            "exampleResult": "https://old.reddit.com/truc",
            "error": null,
            "includePattern": "https://*reddit.com/*",
            "excludePattern": "",
            "patternDesc": "",
            "redirectUrl": "https://old.reddit.com/$2",
            "patternType": "W",
            "processMatches": "noProcessing",
            "disabled": false,
            "grouped": false,
            "appliesTo": [
                "main_frame"
            ]
        },
        {
            "description": "Twitter",
            "exampleUrl": "https://twitter.com/obama",
            "exampleResult": "https://nitter.unixfox.eu/",
            "error": null,
            "includePattern": "https://*twitter.com/*",
            "excludePattern": "",
            "patternDesc": "",
            "redirectUrl": "https://nitter.unixfox.eu/$1",
            "patternType": "W",
            "processMatches": "noProcessing",
            "disabled": false,
            "grouped": false,
            "appliesTo": [
                "main_frame"
            ]
        },
        {
            "description": "Medium",
            "exampleUrl": "https://medium.com/b",
            "exampleResult": "https://libmedium.batsense.net/b",
            "error": null,
            "includePattern": "https://*medium.com/*",
            "excludePattern": "",
            "patternDesc": "",
            "redirectUrl": "https://libmedium.batsense.net/$2",
            "patternType": "W",
            "processMatches": "noProcessing",
            "disabled": false,
            "grouped": false,
            "appliesTo": [
                "main_frame"
            ]
        }
    ]
}

this will not redirect reddit images