When editing an artifact via the tracker artifact view the text editors are instantiated even when the field is not in an edit mode.
It is a waste of client side resources because instantiating the editors is not cheap (especially when the fields use the HTML format) and it can lead to side effects. Indeed in the HTML format the editor might need to adapt the HTML code so it can understand and display it which can lead to changes.
You can see the changes made to a text field without it being switched into the edit mode by submitting an artifact in with an HTML content set to <html><body>A<p>B</p> (use the Source option) and then submit another follow up.