Fenced diagram block renders as plain code instead of a picture
What you are seeing
A fenced diagram block renders as plain code instead of a picture.
#Why it happens
Either the language is not one of the 28 supported diagram languages, or no signed-in session token was available, in which case the block is left as-is with no error.
#What to do
Check the language name against the supported list, and reload the page so the session token is issued. Diagrams do not render for logged-out viewers.
#Limits that apply here
Limit | Value | What happens |
|---|---|---|
Diagram languages | 28 languages | Only actdiag, blockdiag, bpmn, bytefield, c4plantuml, d2, dbml, ditaa, erd, excalidraw, graphviz, mermaid, nomnoml, nwdiag, packetdiag, pikchr, plantuml, rackdiag, seqdiag, structurizr, svgbob, symbolator, tikz, umlet, vega, vegalite, wavedrom and wireviz render as diagrams. |
Session token lifetime | 20 minutes | The short-lived token that lets diagrams render is refreshed automatically before it expires, and again when you return to the window. |
#A few things that catch people out
The language name must match exactly, for example
graphvizrather thandot.A diagram with a syntax error does not draw. Check the code in the editor's live preview.
There is no setting to turn diagram languages on or off, or to use your own renderer.
#Related
Found it? Good.
