Sandboxed iframes are a modern and useful feature to isolate and secure different parts of a web app: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/

Sandboxed iframes are a modern and useful feature to isolate and secure different parts of a web app: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe#attr-sandbox https://developer.mozilla.org/en-US/docs/Web/HTML/Element/if... But thanks for the feedback. The UI can definitely be improved further, but it would be a lot of work to make it look similar to e.g. Google Docs.