Container: copy/pasting content in a HTML doc in source mode does not detect the text and therefore document cannot be saved

[nino-filigran]

Description

Not possible to save in Source mode

Environment

pre release, demo

Reproducible Steps

Steps to create the smallest reproducible scenario:

1. Go in report
2. go to content
3. turn to source mode
4. copy a small enough text so that you don't have to scroll since scroll is broken (cf: Container: in Source Mode, an HTML file is not scrollable  #8687)
5. paste your text
6. you cannot save

Expected Output

I can also save in source mode

Actual Output

I cannot save

Additional information

see video below, starting around 24secs, since at first, I copied a text too long & could not scroll.

Screenshots (optional)

No.saving.content.mp4