mdmap combines simplicity and ease of writing with a visual view not available from a textual layout, allowing mindmap rendition of heading levels (#, ##, ### etc.) while preserving detailed project information in a single file.

https://ca.cloudron.io/app/mdmap

Cool features :

• cross-node links (very rare in mindmaps)
• hover text
• multiple mindmap roots in one diagram (also rare feature)
• customisation embedded in markdown content with controlled metadata attributes