What's new in Mermaid Studio 2026.1.8?

2026.1.8 Release Notes

This release introduces an experimental inspection that surfaces Mermaid.js parser errors directly in the editor, alongside improvements to the export and Markdown preview workflows. Block diagrams receive a major round of enhancements covering navigation, inspections, completions, and formatting, and a broad set of Unicode, compatibility, and parser fixes spans most diagram types.

Highlights

• Mermaid.js Diagnostics (Experimental) — A new inspection collects diagnostics returned by Mermaid.js and shows them inline in the editor, surfacing errors that Mermaid Studio’s built-in analysis does not already cover (disabled by default)
• Export Improvements — Fit-to-window button with auto-fit for large images, background color option for PNG export with theme-aware defaults, and fixed aspect ratio handling
• Markdown Preview Controls — Configurable maximum width/height and inline display options for Mermaid diagrams in Markdown preview
• Block Diagram Support — Node reference resolution in class statements, arrow direction validation, edge label quoting quick fix, undeclared node detection, zero-width composite warnings, CSS property highlighting, auto-indent, and multiline string formatting
• Unicode and Compatibility Fixes — Improved Unicode support and diagnostics across most diagram types, with better error messages and quick fixes for non-portable usage

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Added

• Added experimental Mermaid.js diagnostics inspection that shows errors generated by Mermaid.js in the editor when Mermaid Studio’s built-in diagnostics do not overlap with the reported error range (disabled by default)
• Added fit-to-window button in export preview with auto-fit for large images and fixed aspect ratio
• Added background color option for PNG export with theme-aware defaults
• Added configurable max width/height and inline display option for Mermaid diagrams in Markdown preview
• Added block diagram enhancements: node reference resolution in class statements (go-to-definition, find usages, rename), arrow direction validation, edge label quoting quick fix, undeclared node detection, zero-width composite warnings, CSS property highlighting, auto-indent in composite blocks, and multiline string formatting
• Added completions and validation for icons in Flowchart generalized shape syntax
• Added built-in icon completions for architecture icons
• Added subgraph error isolation and “Add missing ‘end’ keyword” quick fix in flowcharts
• Added pie chart negative number detection

Changed

• Cleaned up Block diagram completions

Fixed

• Fixed completions appearing inside comments across all diagram languages
• Fixed comment/uncomment not working for diagrams of unknown or unsupported type
• Fixed getMermaidSyntaxGuide MCP tool returning “not available” for several diagram types
• Fixed Unicode support across most diagram types, with better error messages and quick fixes for Unicode characters that Mermaid.js cannot render
• Fixed GitGraph not accepting single-quoted strings in branch names and commit attributes
• Fixed Timeline not accepting case-insensitive keywords (Section, SECTION, etc.)
• Fixed init directive (%%{...}%%) causing parse errors in pie chart and ER diagrams
• Fixed sublanguage detection failing when YAML frontmatter is unclosed
• Fixed default diagram theme not matching the editor color scheme
• Fixed various block diagram parsing, completion, and formatting issues
• Fixed requirement diagram rename refactoring for quoted identifiers
• Fixed ER diagram accepting invalid characters in quoted entity names
• Fixed Kanban under-indentation handling with dedicated warning and quick fixes