HTML Preview system should indicate what data comes from the database and what from the file

[mauromsl]

During the typesetting proofing process, it is not clear what elements rendered on the screen came from the database and what elements came from the file.

We should flag the DOM elements depending on their origin

Bonus points: Add a link over the DOM elements that can be edited in Janeway, so that edits can be done by proofreaders or editors.