Update README.md

Ping #218

Author: petecooper

README.md

@@ -1,3 +1,7 @@
+> [!CAUTION]
+> Please do not use the `self-hosted` branch. There is active work underway to resolve some issues.
+> Please refer to https://github.com/textpattern/textpattern.github.io/issues/212 and https://github.com/textpattern/textpattern.github.io/issues/218 for further information.
+
 # Textpattern user documentation repository
 
 This repository drives the [Textpattern user documentation](https://docs.textpattern.com) website. Contributions are welcome and encouraged!
@@ -31,4 +35,4 @@ Proceed as follows:
 4. Click the pencil icon at top-right of the document (the hover text will read, 'Edit this file'). You'll then be in document edit mode.
 5. Make your revisions. Ensure you're following conventions for [strings formatting](https://docs.textpattern.com/brand/user-docs-guide#formatting-interface-strings) and [marking up pre-defined content](https://docs.textpattern.com/brand/user-docs-guide#markup-and-styling) elements.
 6. Hit the **Commit changes** button when finished. This will initiate a pull request. The request will be reviewed (and likely merged) by a repository owner.
-7. Check your changes in the front-end of the document to ensure any formatting or styles used were applied correctly.
+7. Check your changes in the front-end of the document to ensure any formatting or styles used were applied correctly.