| What | Detail |
|---|---|
| Feature | Real-time co-authoring and autosave for .md files |
| Message centre ID | MC1261592 |
| Where | SharePoint Online document libraries and OneDrive for Business |
| Rollout | Standard and Targeted release, phased from late July into August 2026 |
Microsoft 365 message centre post MC1261592 confirms that Markdown files opened in the browser in SharePoint Online or OneDrive for Business now support multi-person editing, the same way a Word or Excel file does. Two admins editing the same README.md no longer means one of them works from a stale copy while waiting for the other to close the file.
What's changing
SharePoint and OneDrive already let users view and edit Markdown with a side-by-side preview pane, a capability that shipped in mid-April 2026. This update adds three things on top of that foundation: autosave (no manual save step, and no more "someone else is editing this file" locks), inline comments anchored to a specific line or block of Markdown, and notifications when a mention or comment needs a response. Multiple people can now have the same .md file open and see each other's changes land in near real time.
For SharePoint admins, the practical effect is that Markdown stops being a second-class file type. Project READMEs, runbooks, and internal wiki-style documentation stored as .md files in a document library get the same collaborative editing experience as .docx and .xlsx already have.
Why this matters for content governance
Markdown files tend to live outside the usual governance conversation. Nobody runs a permissions audit against a README the way they would against a client contract. But once a file type supports real-time co-authoring and comment threads, it accumulates version history, edit metadata, and permission inheritance exactly like any other document. A library full of actively co-authored .md files behaves, for storage and permissions purposes, like any other actively used library.
Version metadata and permission inheritance rules apply to Markdown files the same way they apply to any other file in a SharePoint library, so a library that suddenly fills up with co-authored .md files is a candidate for the same version and permissions housekeeping as any other active library.
Sources: Microsoft 365 Message Center MC1261592 (merill.net archive); Microsoft Community Hub: Introducing Markdown support in SharePoint and OneDrive.