DiagramBlock

Draw

• Four blocks – draw.io diagram, Excalidraw sketch, drawDB schema, Circuit diagram – plus the [diagram id=…] shortcode and a Classic-editor button
• Excalidraw is bundled with the plugin and served from your site, fonts included; draw.io runs from an instance you host (or, if you allow it, the public embed), drawDB and the circuit simulator from the hosts you configure
• The editor opens in a modal over the block editor, the Classic editor and the DiagramBlock library; save keeps the source and an SVG export together

Keep

• A library of every diagram with search, kind filter, thumbnails, authors, views and where each one is used
• Version history on every save with element and size diffs, preview and one-click restore; keep as many versions as you like
• Import .drawio, .excalidraw, drawDB JSON, .svg and Markdown with fenced diagram blocks; export the native file, SVG or Markdown; duplicate, print view, SVG and PNG downloads
• Templates to start from, and a drawDB import of the live WordPress database with relations inferred from …_id columns

Show

• Server-rendered SVG for every kind, cleaned of scripts and external loaders before it is inlined; responsive width per block; captions; lazy loading for large drawings
• A lightbox with zoom, pan, pinch, fullscreen and PNG download; a print view per diagram

Collaborate

• Live collaboration on Excalidraw and draw.io: cursors and scene changes over WebRTC data channels with a polling relay fallback, presence badges, no extra server
• Roles that may create and edit diagrams; managers see everything

Integrate

• REST diagramblock/v1 (public reads of published diagrams and templates; writes with cookie + nonce or an application password), wp diagramblock list|export|import|templates|render, a Site Health check and an activity log