I want Markdown files on my computer to open in [the chosen, installed application].
Change the default application for this file type. Use [a specific file] to check it.

After the change, open this file with an ordinary double-click in the file manager
and check that its text is visible, not only the program window.
Do not change the document’s content or location.

If only another method works, such as a special link, describe it separately.
Do not treat it as confirmation that double-clicking works.

If an additional configuration step is needed, explain its scope.
At the end, state: what was changed, which file was checked, and whether it opened.