Support edition of iframe elements in the annotation editor

[dnknn]

👆contenteditable="true" Edit mode, not work in iframe.
Currently it can be implemented manually. e.g. contenteditable="true" into iframe body html

[gildas-lormeau]

Unfortunately, the code from "Typio Form Recovery" would not work in the annotation editor of SingleFile. Actually, for security reasons, I've made sure that the page displayed in the annotation editor is totally sandboxed. I want to avoid that an eventual "malicious" script would access to the API used by extensions (which are quite powerful). The problem is that the sandbox is also quite effective and also blocks access to frame contents from the SingleFile code itself...

[dnknn]

Okay, it's not a big problem. After all, iframes are very special, so don't worry about it.

[gildas-lormeau]

We can let the issue open though ;)

[gildas-lormeau]

Even if this issue technically complicated to fix, I prefer to keep it open as a reminder.