Editor · JetBrains plugin
Mermaid Companion
FreemiumDiagrams
Syntax highlighting and real syntax validation for .mmd/.mermaid diagram source files (flowchart, sequence, and class diagrams).
The gap it fixes
Mermaid Studio (JetBrains Marketplace id 29870), 11,168 downloads, paid, vendor Tachi Labs. Real, verbatim reviewer complaints:
- "the plugin shows false warnings for valid non-ASCII subgraph identifiers... e.g. for subgraph á it warns for 'Subgraph identifier á contains special characters...'" (2026-02-16, 2026-02-23 -- the same bug persisted across two separate reviews)
- "shows false errors for valid node shapes where the node contains non-ASCII characters" -- valid nested quotes, accepted by mermaid.live, marked as an error
- "It opens and shows me a bunch of icons on page. That's it. No other functionality at all." (1 star, 2026-03-30)
Facts and pricing
- Category
- Editor
- Pricing
- Freemium
- Platform
- IntelliJ-family
- First published
- 2026-08-27
- Marketplace ID
- #33340
- Repository
mermaid-companion- Growth
- ▲ +920.8% since 2026-08-18 (72→735)
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Select an identifier (or just place the caret on one: no selection needed) and instantly convert it between camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE.
Download and star counts as of 2026-10-18, refreshed twice daily from the JetBrains Marketplace and GitHub APIs.