GitHub + Mermaid
Extension Delisted
This extension is no longer available in the official store. Delisted on 2025-09-15.
A browser extension for Chrome, Opera & Firefox that adds Mermaid language support to GitHub.
Create diagrams using code blocks on GitHub issues, Pull Requests, or .md files:
```mermaid
graph TD;
A-->B;
A-->C;
B-->D;
C-->D;
```
Visit https://mermaidjs.github.io/ for more information about Mermaid language syntax.
Latest reviews
Unable to modify the sites it works with, preventing me from using it with the private github server I need to use. Unable to comment on the quality of the plugin otherwise
Parse error on line 2: ...TD subgraph Sources["Project Groups"] ----------------------^ Expecting 'SEMI', 'NEWLINE', 'SPACE', 'EOF'.... Please update the mermaid version this uses, its got to be a few years out of date.
It's a nice extension, but the underlying version of mermaid hasn't been updated in a while and is missing newer abilities. This make it less useful as it doesn't adhere to the current spec.
not support classDiagram!!!
I like the idea but it does not support newer features such as autonumber or color values of objects. For example: rect rgb(0, 0, 100)
Like it for sequence diagrams but it's failing on stateDiagram and classDiagram that works perfectly well within VSCode but fails in Chrome when viewing the same README.md file. It is difficult to debug because there are no map files and the error is in the parsing, which is difficult to make sense of. Same content also fails in a gist: https://gist.github.com/ca0v/d019b29e044598d6b386ccdc81b6887f
Awesome job!
Works perfectly well in all the cases: PR descriptions, MD diff preview, review comments, ... Awesome job!
