Hint:
Some RWD pages (let's say with "incomplete RWD") are experiencing iframe overflow (iframe does not fit into the iframe-container).
Unfortunately, we can't fix that from the iframe outside and to solve this issue, document inside iframe requires at least:
body {
/* Resolves iOS overflow rendering bug */
max-width: 100vw !important;
}
Optionally, you can scale iframe document as below.