How do I get started?
Click the menu bar icon. On first launch Margin asks you to choose a vault folder: pick any folder of Markdown files, or an empty one to start fresh. Margin reads the .md files sitting at the top level of that folder and leaves subfolders alone.
My notes are not listed after I reopened the app.
Choose the vault folder again from Preferences. macOS grants an app access to a folder when you pick it, and Margin keeps a bookmark so it can reopen the same one later. If that bookmark goes stale, which can happen when the folder is moved, renamed, or lives on a drive that was not mounted at launch, picking the folder once restores access.
Where is the save button?
There is not one. The body saves about half a second after you stop typing, and renaming the title renames the file a moment after you stop. Closing the panel or quitting writes anything still pending, so you can dismiss the window mid-sentence and nothing is lost.
How do the hotkeys work?
Open Preferences with the gear in the list header, or right-click the menu bar icon and choose Preferences. You can record one shortcut that opens your most recent note and another that opens a fresh note, both with the cursor already in the body. Neither has a default, so that Margin never takes a combination you already use, which means they do nothing until you set them.
The title field and the filename are the same thing?
Yes. The title of a note is the name of its file, so renaming one renames the other. That is what keeps the folder readable outside Margin: your notes look exactly like what they are.
How do I delete a note?
Swipe a row left in the list, or right-click it and choose Move to Trash. The file goes to the macOS Trash and can be recovered from there, and an Undo bar stays up for the rest of the session.
The window disappears when I click somewhere else.
That is deliberate. Margin is a panel that gets out of the way when it loses focus, and your work is already on disk by then. Click the menu bar icon to bring it back.
Where are my notes stored?
In the folder you chose, as ordinary Markdown files. Margin has no account, no server, and no library of its own, and it can reach nothing on your disk but that folder. See the privacy policy for the full picture.
Contact
Email cody@adventinnovation.com with your Mac model, the macOS version, and what you were doing when the problem happened.