Your bug report writes its own headline
Start a bug or feature draft and the composer shows a Markdown skeleton. Put a top-level heading on top and the app turns it into the issue title, then strips it from the body.
You type the bug command into the composer and the grey hint becomes a Markdown skeleton. It has a title line, Steps, and Expected vs. actual. Start a feature draft instead and you get Problem and Proposal. The instant you start typing, the ghost text vanishes, but the box holds the skeleton's height, so nothing jumps under your cursor.
Credit goes to paulinevos, who gave the composer those two templates and taught the server to read them. On submit, the app parses your draft as Markdown and lifts the first top-level heading out as the issue title. It trims that title to 256 characters and flattens bold and links to plain text. Then it cuts those heading lines from the body. Lists, tables, checkboxes, and code fences reach GitHub just as you typed them. A heading marker inside a code block or quote does not count. Skip the heading and the first line becomes the title, still sitting in the body.
There is one catch. The heading needn't be first. Drop an extra top-level heading halfway down your report and the app hoists it into the title and deletes it from the body, so the sections above it open the issue and your later heading is gone.