Just tried out exporting notes as Markdown from the Notes app in macOS Tahoe Beta 2.

You can select multiple notes, but only the first selected note is exported.

If you are trying to export multiple notes (10, 20, 50, etc.), this is incredibly tedious and time consuming.

Filed as FB18462239 'Notes app does not export all selected notes'

@jamesdempsey The indie tool "Exporter" converts your complete Notes database (or parts) into a folder of .md files. It does not require macOS 26, and also nicely exports tables as MarkDown inline tables (macOS 26 writes tables as .csv files, linked to by the .md).
https://apps.apple.com/us/app/exporter/id1099120373?mt=12
‎Exporter

‎Export notes from Notes.app - Notes can be exported to markdown or HTML format. - Creation & modification dates of notes are preserved. - Notes are stored in directories named after the notebooks in which they are stored in Notes.app. - Notes in same notebook having same name are renamed to avoid ol…

Mac App Store