Related to this question dated 5 years ago and where it is stated that "Google Docs doesn't have invisible placeholders at this time, but it has bookmarks."
MS Word has 'content controls' that allow the insertion of any kind of text with a user-controlled tag. This is great for inserting in-text bibliographic references from an outside source (which is what my add-in does) because I can then not only add the reference itself to the control but also a unique identifying tag that allows me to tie that reference to its source and easily find it and other controls in the document. What this means in practice is that I can change at the click of a button the bibliographic style of all the in-text references and appended bibliography (e.g. APA to Harvard and back again). I can do this in my Word add-in because of the content control.
I can't figure out how to do this in google docs or even if it is possible. I can't find (but might have overlooked) any of the invisible placeholders that, five years ago, where not available "at this time". I could try using bookmarks but I don't believe it is possible to label them with an identifying tag other than the automatic one generated by google. I could use a combination of this automatic ID and getDocumentProperties() to keep track of things but this immensely complicates matters. An invisible placeholder or tag wrapped around the in-text reference could do the trick too.
My question then is, are there now any invisible placeholders or even content controls similar to Word's?
