Collapsible lists in Google Docs without having to use Heading style?

Question

I'm looking for a way to collapse text in Google Docs without relying on headings. I've been using OneNote and that set up works well, but I write in Gdocs and want to streamline my workflow.
 My note hierarchies aren't based on where they fall in the large project/paper, they are based on topic or concept. The paper structure/outline comes later once I know what content I'm dealing with. The content is coming from varied sources. I sort and synthesize notes later to establish common themes.
 Requiring heading formats for collapsing text is impractical in this stage because:
I don’t yet know the final structure, and what level in a hierarchy the information taken in notes will fall
The content might belong to different hierarchical levels, depending on the source
When reorganizing information from the larger set of notes, the heading format interferes with my workflow when reorganizing information, messing up what is collapsed under what heading.
What I need is a way to make collapsible lists independent of a document hierarchy so I can sort (drag and drop) the collapsed lists later in my process.
 OneNote allows for this, but I write in google docs. Problem with transferring: 
Time consuming
Extra steps = greater margin for error
Formatting gets messed up when copied/pasted
Help??

MsJenniferS · Accepted Answer

The Collapsible headings feature only works for text formatted as a title or heading.
You can share feedback directly with the Docs team by opening a Docs file and going to Help > Help Docs improve. The Google Product teams review all feedback sent to them and use it to make future improvements to the app.
-MsJenniferS