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 A collaborative wiki built on [ATProto](https://atproto.com). Knowledge grows together.
 
-<!-- TODO: screenshot or demo gif -->
-
 ## What is Lichen?
 
 Sign in with your Bluesky account, create wikis, and write in plain markdown with `[[wikilinks]]`. Your data lives on your own PDS: it persists independently of this app, and your Bluesky identity works everywhere on ATProto.
@@ -17,6 +15,36 @@ Sign in with your Bluesky account, create wikis, and write in plain markdown wit
 - Multilingual UI (English and French)
 - Self-hostable: deploy your own instance, fully independent
 
+## Markdown support
+
+Notes are plain markdown: CommonMark and GFM, plus the Obsidian extensions people actually use. No proprietary format, so a wiki exports into an Obsidian vault or a static site generator without a rewrite.
+
+| Feature | Lichen | Obsidian | GitHub (GFM) |
+|---|:--:|:--:|:--:|
+| Tables | ✅ | ✅ | ✅ |
+| Strikethrough `~~text~~` | ✅ | ✅ | ✅ |
+| Task lists `- [ ]` | ✅ | ✅ | ✅ |
+| Footnotes `[^1]` | ✅ | ✅ | ✅ |
+| Highlight `==text==` | ✅ | ✅ | — |
+| Callouts `> [!note]` | ✅ | ✅ | ✅ |
+| Comments `%%hidden%%` | ✅ | ✅ | — |
+| Math `$…$` / `$$…$$` | ✅ | ✅ | ✅ |
+| Syntax-highlighted code | ✅ | ✅ | ✅ |
+| Heading anchors | ✅ | ✅ | ✅ |
+| Bare URLs autolinked | ✅ | ✅ | ✅ |
+| Wikilinks `[[note]]` | ✅ | ✅ | — |
+| Aliases `[[note\|label]]` | ✅ | ✅ | — |
+| Heading links `[[note#Heading]]` | ✅ | ✅ | — |
+| Cross-wiki `[[@handle/wiki/note]]` | ✅ | — | — |
+| Backlinks | ✅ | ✅ | — |
+| YouTube embed from a bare URL | ✅ | ✅ | — |
+| Transclusion `![[note]]` | — | ✅ | — |
+| Block references `[[note#^id]]` | — | ✅ | — |
+| Tags `#tag` | — | ✅ | — |
+| YAML frontmatter properties | — | ✅ | shown as a table |
+| Raw HTML | — by design | ✅ | sanitized subset |
+
+
 ## How it works
 
 Contributors write directly to their own [Personal Data Server](https://atproto.com/guides/glossary#pds) via OAuth. The Lichen appview ingests those records from the network firehose, assembles wiki state, and serves reads. Your data is never locked in: it follows you across the ATProto ecosystem.