Export a document you can inspect
Use a copy of the Markdown Handoff Kit. Its specification links to acceptance criteria and a local SVG. When a compatible app offers HTML export, save the page beside the source, then open the .html file in a browser. Compare headings, image, links and code with the original.
Stay on the rendered page. File → Export as HTML is unavailable while you are editing, and unavailable when the document is empty. It has no keyboard shortcut. Choose it, then save in the panel. The panel suggests the document name with .html, in the document’s folder.
Aero Markdown writes one local HTML file: the rendered article and the reader stylesheet. A readable png, jpg, jpeg, gif, or webp inside the opened folder is embedded in that file. Download and checkout are not available yet. The Mac app is not publicly available yet. This page describes that command; it is not a report from a public release.
Test the actual delivery
Open the saved HTML away from the Markdown folder. An embedded png, jpg, jpeg, gif, or webp still shows, because the picture is inside the file. An SVG does not: it stays a missing figure and is not read into the file. A remote image is not fetched, with or without a network connection. An image the app cannot read stays a missing figure. Mermaid stays the diagram source, and math stays the formula text, because the file includes no scripts. A website link can remain clickable and still needs a connection. If the recipient must edit, send the Markdown and its assets as well.
The portable docs lab helps you practice with relative paths. For a fixed reading copy, compare this with PDF export and the handoff checklist. This guide gives a QA procedure, not a claim that a release build has passed it.