I've recently upgraded to the latest version of Thunderbird (68.2.2), and updated Clippings to V5.7 to keep things compatible. I'm trying to create an HTML clipping, and it pastes back into my email as plain text.
The method I am using is this:
1) New email message
2) Paste in HTML form from a Word doc
3) Select all text
4) Rt click, New from Selection.
I've also tried pasting the text in the Clippings manager.
The results are the same, when I paste the saved clipping into a new email, the formatting reverts to plain text.
Open to suggestions, I'd really like to have HTML support.
-dhs