It's very common to indicate to the user that they can "edit in place" by changing the style of the editable content when hovered over (e.g. adding a yellow background, "click to edit" tooltip, pencil icon appearing, etc). This means the user doesn't discover the functionality until they just happen to hover over something editable.
In my web application, I have a page that has upwards of 25 editable fields. I want the user to know just by looking at the page that they can make edits. Additionally indicating the ability via hover would just be an added bonus.
I've thought about dotted underlining each editable content, as this usually implies "hint" or "hover on me" (like the image below):
The problem with this though is that it doesn't imply "i'm editable", it instead just encourages the user to hover (without them knowing why), and then the hover will have the indicator. Maybe this is OK? At least they'll discover it faster. But is there a better way?
The reason the page isn't a permanent edit form is because users want to view-only the information just as often as they want to edit it. But when they do want to edit, they usually just want to quickly edit a single field. Also, I am not worried about mobile, as my users are solely on desktops.
<abbr>element - showing abbreviations. It is somewhat misused for hover, so much so that the original purpose is overlooked.