Fix note editor long content overflow

[windingwind]

Before:

After:

[dstillman]

Can we use stretch?

https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Mozilla_extensions#width_min-width_and_max-width

[windingwind]

the stretch is only available after fx146 https://caniuse.com/?search=width%3A+stretch

[dstillman]

OK, let's add a comment to replace it, then.

[windingwind]

done