Weekly GitHub Report for Mermaid

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Table of Contents

• I. News
  • 1.1. Recent Version Releases
  • 1.2. Other Noteworthy Updates
• II. Issues
  • 2.1. Top 5 Active Issues
  • 2.2. Top 5 Stale Issues
  • 2.3. Open Issues
  • 2.4. Closed Issues
  • 2.5. Issue Discussion Insights

• III. Pull Requests
  • 3.1. Open Pull Requests
  • 3.2. Closed Pull Requests
  • 3.3. Pull Request Discussion Insights

• IV. Contributors
  • 4.1. Contributors

I. News

1.1 Recent Version Releases:

The current version of this repository is @mermaid-js/[email protected]

1.2 Version Information:

On March 25, 2025, a minor update was released introducing a new Radar Chart feature, enhancing the charting capabilities of the platform. This addition reflects ongoing efforts to expand visualization options.

II. Issues

2.1 Top 5 Active Issues:

We consider active issues to be issues that that have been commented on most frequently within the last week. Bot comments are omitted.

1. [TYPE: BUG / ERROR] [STATUS: APPROVED] Flowchart: Mardown is not interpreted when it is mixed with a text which contains a math formula: This issue addresses a problem where markdown formatting is not rendered correctly when mixed with math formulas in flowchart node labels, causing the markdown to appear as plain text instead. The root cause is identified in the rendering logic where labels containing math formulas bypass markdown processing, leading to markdown and icon syntax being displayed literally instead of being interpreted.

   • The comments confirm the bug and link it to a related issue, explain the technical cause involving the rendering pipeline skipping markdown processing for math-containing labels, and discuss a planned fix that selectively applies markdown rendering only to non-math segments; a pull request has been submitted to address the problem.
   • Number of comments this week: 2

2. [STATUS: TRIAGE] Flowchart htmlLabels do not wrap on fractional devicePixelRatio: exact-equality bbox.width === width is fragile: This issue describes a bug in Mermaid's flowchart rendering where HTML labels fail to wrap correctly on devices with fractional devicePixelRatio due to a fragile exact float equality check between the bounding box width and the wrapping width. This causes labels to overflow their nodes in Chrome/Blink browsers on HiDPI fractional scaling displays, while Safari and integer scaling setups render correctly; the problem is fixed by replacing the strict equality check with a tolerant comparison.

   • Commenters confirmed the bug and the proposed fix involving a tolerant width comparison, shared detailed reproduction steps and environment specifics, and verified the issue persists in recent Chrome versions but is resolved by the suggested patch.
   • Number of comments this week: 2

3. [TYPE: ENHANCEMENT] [TYPE: NEW DIAGRAM] BPMN support: This issue requests support for BPMN (Business Process Model and Notation) diagrams in Mermaid to enable users to create and maintain business process definitions within tools like Notion using Mermaid’s text-based diagramming capabilities. The discussion centers around scoping the feature to focus initially on Level 1 BPMN elements for documentation and communication purposes, with multiple community members sharing prototypes, syntax ideas, and use cases while debating whether BPMN support should be integrated as a core Mermaid feature or as an external plugin.

   • The comments reveal strong community interest in BPMN support, emphasizing a pragmatic MVP scope focused on Level 1 elements and swimlanes; several independent prototype implementations and syntax proposals have been shared, but maintainers have yet to decide on a unified approach or integration path, leading to some fragmentation and calls for consolidation of efforts.
   • Number of comments this week: 1

4. [TYPE: BUG / ERROR] [STATUS: TRIAGE] C4-PlantUML syntax shows [ENTERPRISE] stereotype for System_Boundary: This issue reports a bug where the C4-PlantUML syntax incorrectly displays the stereotype [ENTERPRISE] for a System_Boundary element instead of the expected [SYSTEM] label. The user provides steps to reproduce the problem and expects the diagram to show [SYSTEM] beneath the system boundary title when generated.

   • The comments confirm the source of the error in the parser code and request an example diagram, which is provided. Further discussion reveals that the issue has already been fixed in the current development branch, with the stereotype rendering behavior now configurable and the legacy bug no longer present.
   • Number of comments this week: 1

5. [TYPE: BUG / ERROR] [STATUS: APPROVED] [INTERNALS: RENDERER] [GRAPH: C4] Bug: namespace prefix xlink for href on image is not defined: This issue reports a bug in mermaid version 9.4 where the SVG output for C4 diagrams includes <image> elements with xlink:href attributes but lacks the necessary xmlns:xlink namespace declaration, causing the SVG to render incorrectly. The discussion reveals that this problem was addressed in a later update by removing the use of <image> elements entirely in favor of <path> elements, thereby eliminating the need for the xlink namespace and fixing the rendering issue without adding the namespace declaration.

   • The comments include attempts to reproduce the issue, explanations about SVG namespace requirements and innerHTML insertion problems, suggestions for workarounds, and confirmation that the bug was ultimately fixed on the develop branch by replacing <image> elements with <path> elements, removing the dependency on the xlink namespace; a note was also made that future features involving sprites might reintroduce the need for the namespace.
   • Number of comments this week: 1

2.2 Top 5 Stale Issues:

We consider stale issues to be issues that has had no activity within the last 30 days. The team should work together to get these issues resolved and closed as soon as possible.

As of our latest update, there are no stale issues for the project this week.

2.3 Open Issues

This section lists, groups, and then summarizes issues that were created within the last week in the repository.

Issues Opened This Week: 3

Summarized Issues:

• Test suite timeout and CI issues: The continuous integration end-to-end test runs the entire mmd-snapshots test suite on a single shard, causing the job to exceed the 30-minute timeout limit and be cancelled. This results in misleading failure reports and intermittent impacts on multiple contributors.
• issues/8235

• Parsing bugs in sequence diagrams: A parsing bug occurs when a space between an actor's name and its configuration object causes the line to fail parsing, while similar syntax without the config object tolerates trailing whitespace. This inconsistency leads to confusing errors and suggests the parser's lookahead rules need adjustment to allow optional spaces.
• issues/8255

• Error message clarity for maxEdges limit: The current error message for exceeding the maximum number of edges (maxEdges) is vague, showing "Syntax error in text," which misleads users into thinking there is a syntax problem. An enhancement is requested to provide a clearer and more specific error message.
• issues/8262

2.4 Closed Issues

This section lists, groups, and then summarizes issues that were closed within the last week in the repository. This section also links the associated pull requests if applicable.

Issues Closed This Week: 1

Summarized Issues:

• maxTextSize configuration issue: After updating to version 12.0.0, the maxTextSize configuration option in Mermaid fails to prevent the "Maximum text size in diagram exceeded." error in large flowcharts. Attempts to override the limit with both fixed and unlimited sizes do not resolve the problem, causing persistent errors.
• issues/8260

2.5 Issue Discussion Insights

This section will analyze the tone and sentiment of discussions within this project's open and closed issues that occurred within the past week. It aims to identify potentially heated exchanges and to maintain a constructive project environment.

Based on our analysis, there are no instances of toxic discussions in the project's open or closed issues from the past week.

III. Pull Requests

3.1 Open Pull Requests

This section provides a summary of pull requests that were opened in the repository over the past week. The top three pull requests with the highest number of commits are highlighted as 'key' pull requests. Other pull requests are grouped based on similar characteristics for easier analysis. Up to 25 pull requests are displayed in this section, while any remaining pull requests beyond this limit are omitted for brevity.

Pull Requests Opened This Week: 15

Key Open Pull Requests

1. Replace default fonts with OSS fonts: This pull request replaces the default restricted-license fonts Tahoma MS and Arial used in Mermaid with open-source, metrically compatible web fonts—Atkinson Hyperlegible Next and Arimo respectively—while updating the documentation and ensuring compatibility with existing fonts through tests.

• URL: pull/8240

• Associated Commits: 952e1, a06c8, 840b7, 92731, 83268, 6d38a, 8f05c

2. fix(flowchart): keep ELK edge labels centered: This pull request fixes the positioning of ELK edge labels in flowcharts by keeping them centered when the flowchart.subGraphTitleMargin is configured, introducing a layout-specific vertical label offset in the common renderer that ELK sets to zero to align labels accurately without altering ELK's layout data or duplicating logic, thereby resolving issue #7341 with improved test coverage and no regressions.

• URL: pull/8238

• Associated Commits: 8f636, 6f04b

3. fix(tidy-tree): support Mermaid 12 peer dependency: This pull request updates the @mermaid-js/layout-tidy-tree package to widen its peer dependency range to support both Mermaid versions 11 and 12, includes a patch changeset, and validates the changes through semver checks, unit tests, linting, formatting, and a successful build on Node 22.22.0.

• URL: pull/8248

• Associated Commits: cb662, dd090

Other Open Pull Requests

• Parser and Lexer Fixes: Multiple pull requests address parsing and lexing issues in Mermaid diagrams. These include fixing lexer rules to allow hyphens in actor and participant names with attached configurations, and extending lexer token ranges to support unquoted accented Latin characters in chart axis labels and titles, ensuring consistent and correct parsing across different diagram elements.
• [pull/8249, pull/8256]

• HTML Label Rendering Improvements: Several pull requests fix rendering issues related to HTML labels in Mermaid diagrams. They introduce a one-pixel tolerance for fractional HTML label widths to preserve text wrapping on devices with fractional pixel ratios and fix rendering of HTML labels containing both Markdown and math spans by isolating math expressions during Markdown processing.
• [pull/8233, pull/8242, pull/8247]

• Sequence Diagram and Annotation Fixes: Pull requests improve sequence diagram rendering by fixing sizing issues of KaTeX-rendered Note over annotations and resolving parsing errors related to actor and participant names. These changes ensure correct note box dimensions and consistent name acceptance in sequence diagrams.
• [pull/8229, pull/8249]

• Security Enhancements in Styling: A pull request introduces a safeColor function to sanitize palette colors before CSS interpolation, preventing CSS injection vulnerabilities from malicious palette values. This security measure is applied across multiple style modules and is verified with comprehensive unit tests.
• [pull/8234]

• Continuous Integration and Testing Updates: Updates to the CI workflow shard scoped end-to-end test runs into two shards to distribute snapshot workload and avoid timeouts, maintaining existing job limits and success criteria.
• [pull/8236]

• Community Integrations and Documentation: New community integrations are added, including AtlasDocs for live Mermaid code previews and Sanctuary Reader for browser-based Markdown rendering of Mermaid blocks. Documentation and spellcheck ignore lists are updated accordingly to reflect these additions.
• [pull/8258, pull/8243]

• Encoding and Rendering Fixes: A fix replaces window.btoa with a Unicode-safe toBase64 helper to encode edge data points, preventing rendering failures caused by non-Latin1 characters in serialized edge points.
• [pull/8251]

• Contributing Guide and Environment Updates: The contributing guide is updated to raise the minimum required Node.js version to 22.12.0 and adjust the optional pnpm env use command to select Node.js 24, with no source code changes beyond documentation.
• [pull/8257]

3.2 Closed Pull Requests

This section provides a summary of pull requests that were closed in the repository over the past week. The top three pull requests with the highest number of commits are highlighted as 'key' pull requests. Other pull requests are grouped based on similar characteristics for easier analysis. Up to 25 pull requests are displayed in this section, while any remaining pull requests beyond this limit are omitted for brevity.

Pull Requests Closed This Week: 12

Key Closed Pull Requests

1. Release/12.0.0: This pull request releases version 12.0.0 of the Mermaid diagramming library, making the ELK layout engine the default for most diagrams by bundling it directly into Mermaid, introducing new diagram types such as UML use case and agentflow-beta diagrams, and delivering numerous enhancements and bug fixes to layout, theme, and rendering consistency across diagram types.

• URL: pull/8211

• Associated Commits: 5d90f, 0dc0d, 5f9ce, 99525, 756ae, b134d, 7ee4c, d4bea, 1246a, 1befa, 3b092, a2448, 6f9e8, 785ca, 5e8f8, 68a70, 5099c, aa72e, fef9e, 294c3, 7f911, 8d565, 1348b, cd8b6, b4463, 9bd2e, db17c, f5af4, ce030, d1a19, 524b7, 25b2b, adc63, 31e62, b02f1, cb9e0, 5f501, 0ad30, b8325, 63440, 38024, 53f45, 721b8, 2878c, 5f8ef, 0454b, 94b02, 90534, 0ec29, e94c3, cac6b, c1c11, 2120b, 62064, 121ca, 13bd7, 48d83, 82def, 3d258, 29354, 6485d, 20afb, 22779, 813c7, 20d4a, 1eb23, 1634e, 24ddc, 6fc90, a2a62, 012e1, be6fa, b2de3, 90d57, 0afa5, 5ff81, c4b51, c5d4b, ca8fc, 8c066, e36ef, 7e284, d76e2, c8a4b, e947c, 3569e, 846fd, 5660f, ea819, 2bac3, 238c2, fef70, 828ed, 72519, b9939, 44f65, 563d1, f8037, cbc68, bfc03, 1cebd, d2274, 9018d, 1d01a, a240b, b8e6f, b4253, 59c61, 91036, 7a804, 29597, 23a12, 236a9, 78001, e5287, 8cc33, 9b3fc, d6a4f, cf8d2, 32775, a3788, 4e00c, fa6a8, a7831, b9fa6, 0d75e, 03204, ee33b, fe0e2, a31ec, 93edd, 1488b, 9cbba, e23d0, 9d618, 3d010, 3a8b3, d46cb, 21304, 66420, f4d14, e1fb5, 92876, 24068, 4ec49, b979e, 503b5, a19bd, 33cf3

2. Merge back 12.0.0 to develop: This pull request merges the 12.0.0 release branch back into the develop branch, incorporating major updates such as the adoption of ES2024 and Node.js 22.12+ targets, the bundling and default use of the ELK layout engine with improvements to diagram routing and rendering, enhancements to shape sizing and label wrapping, removal of legacy configurations, updated themes and documentation, expanded test coverage, and various fixes and CI improvements to ensure release verification and package publishing.

• URL: pull/8245

• Associated Commits: bc98c, ae451, 0d779, e473b, f2388, b0582, 183a2, 422b3, e36b8, 9d8ba, b708a, 45b9c, 3c21b, 15eb6, e2aab, 98465, e6910, b7395, 9551e, 90fc2, 76d1d, d282c, d5a81, ff842, 9d152, ad980, dc2e4, 147a4, 6e37d, 223be, 03040, 1997a, 01b85, 8a903, 83828, e1cc7, dd65c, 96be5, bf702, 87dae, 98a09, 661f7, 67af1

3. fix(quadrant): ensure quadrant titles wrap and stay within bounds (#6562): This pull request addresses issue #6562 by implementing a fix that ensures quadrant titles in quadrantChart are left-aligned, automatically wrapped using tspan elements, and constrained to stay within the quadrant's boundaries both horizontally and vertically, thereby preventing overflow and misalignment of long or multi-word titles.

• URL: pull/6583

• Associated Commits: 677a9, babea, fcc1a, 3f190, 6c472, e607e, 65722, 440fa, f0969

Other Closed Pull Requests

• Flowchart test fixes and additions: This topic includes fixes to incorrect paths and filenames for Dagre-specific flowchart tests and the addition of a new ELK flowchart test. It also updates test organization to prevent empty screenshots from appearing in Argos, improving test reliability and coverage.
  pull/8244

• Documentation updates: These pull requests fix contributor username errors and ordering issues in contributor tiles, and add detailed information about default fonts, web font setup, and font installation for proper Mermaid diagram rendering. The documentation improvements enhance clarity and usability for contributors and users alike.
  pull/8253, pull/8241

• Gantt chart warnings: This pull request adds warnings for unresolved after or until task ID references and invalid task end values in Gantt charts. These warnings make previously silent failures visible without altering existing scheduling fallback behavior, improving user feedback during chart creation.
  pull/8254

• New Schema3D integration: This pull request adds Schema3D, a browser-only 3D visualizer for Mermaid ER diagrams and related schemas using shareable URLs without live database connections, to the Community integrations documentation. This expands Mermaid's visualization capabilities with a new community-supported tool.
  pull/8261

• Packet diagram bit order option: This pull request introduces a packet.bitOrder option allowing users to switch bit numbering direction from ascending to descending order. This supports conventional hardware register layouts by mirroring rows without changing field declarations or widths.
  pull/8250

• Sequence diagram parser fix: This pull request fixes the sequence diagram parser to allow optional whitespace before a participant's @{ ... } configuration object by modifying the lexer rule's lookahead. This prevents parse errors and improves syntax flexibility in sequence diagrams.
  pull/8259

• Flowchart shape sizing fix: This pull request corrects sizing of non-rectangular flowchart shapes by basing dimensions on label height and diagonal instead of width alone. It removes an obsolete wrapping exemption and adds tests to ensure labels fit within shape outlines, fixing issues with long labels causing clipping or excessive width.
  pull/8232

• Unit test fix for appearance docs: This pull request modifies a unit test assertion to accept either a placeholder or a concrete released version string in the appearance docs marker. This change unblocks the unit-test job on a related pull request and ensures tests pass before and after version substitution in documentation.
  pull/8239

3.3 Pull Request Discussion Insights

This section will analyze the tone and sentiment of discussions within this project's open and closed pull requests that occurred within the past week. It aims to identify potentially heated exchanges and to maintain a constructive project environment.

Based on our analysis, there are no instances of toxic discussions in the project's open or closed pull requests from the past week.

IV. Contributors

4.1 Contributors

Active Contributors:

We consider an active contributor in this project to be any contributor who has made at least 1 commit, opened at least 1 issue, created at least 1 pull request, or made more than 2 comments in the last month.

If there are more than 10 active contributors, the list is truncated to the top 10 based on contribution metrics for better clarity.

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