This plug-in allows you to indicate through front matter that a note should always be opened in a certain view mode. This is done through the key obsidianUIMode, which can have the value source or preview.
Add below snippet (front matter) to your note ...
---
HeaderState: fold
---
... and this will force the note to fold all headings & lists.
Similar, ... add below snippet to your note ...
---
HeaderState: unfold
---
... and this will force the note to unfold all headings & lists.
This plug-in also ensures that a note is always opened in the configured default mode (suppose the Obsidian setting has "preview" as default mode but the pane is currently in "source" mode, then opening a new note in that same pane will open in "preview" mode).