
Hamish Willee developed and maintained browser extension APIs and documentation across the mdn/content and mdn/browser-compat-data repositories, focusing on cross-browser compatibility and developer experience. Over 19 months, he delivered features such as tab grouping, storage enhancements, and new APIs like userScripts and StorageArea.getKeys(), while also fixing bugs affecting extension reliability and data accuracy. Using JavaScript, JSON, and CSS, Hamish aligned API behavior across Chrome, Firefox, and Safari, clarified permissions and security policies, and improved technical documentation. His work demonstrated depth in API design, data modeling, and technical writing, resulting in more robust, maintainable, and accessible browser extension platforms.
April 2026 (mdn/content): Delivered key Firefox Extensions reliability improvements and policy-aligned documentation. Key outcomes: - Restored CSS import functionality for Firefox extensions (Bug fix). - Updated docs to clarify minimum supported Firefox extension version due to root certificate expiration (Feature). Business value: reduced extension load/import errors, ensured compatibility with security policy, enabling developers to ship extensions confidently. Technical achievements: debugging import pipelines, fixing CSS import flow, updating docs and notes for strict_min_version, demonstrated proficiency in JavaScript/CSS extension contexts and documentation standards.
April 2026 (mdn/content): Delivered key Firefox Extensions reliability improvements and policy-aligned documentation. Key outcomes: - Restored CSS import functionality for Firefox extensions (Bug fix). - Updated docs to clarify minimum supported Firefox extension version due to root certificate expiration (Feature). Business value: reduced extension load/import errors, ensured compatibility with security policy, enabling developers to ship extensions confidently. Technical achievements: debugging import pipelines, fixing CSS import flow, updating docs and notes for strict_min_version, demonstrated proficiency in JavaScript/CSS extension contexts and documentation standards.
March 2026: Across the MDN repos, delivered cross-browser, security-conscious enhancements that boost reliability, security, and developer productivity. Key features include Tabs API split-view support (splitViewId) for unified multi-view tab management; programmatic browser action popups; and enhanced tab-enabled isEnabled. Major fixes include security hardening disallowing dynamic code execution in moz-extension documents and focus-aware popup behavior to align Firefox with Chrome/Safari. Supporting work on MV3 alignment and Safari shortcut key documentation improves developer onboarding. Technologies involved: JavaScript/TypeScript, WebExtensions APIs, cross-repo collaboration, and lint/code-review discipline.
March 2026: Across the MDN repos, delivered cross-browser, security-conscious enhancements that boost reliability, security, and developer productivity. Key features include Tabs API split-view support (splitViewId) for unified multi-view tab management; programmatic browser action popups; and enhanced tab-enabled isEnabled. Major fixes include security hardening disallowing dynamic code execution in moz-extension documents and focus-aware popup behavior to align Firefox with Chrome/Safari. Supporting work on MV3 alignment and Safari shortcut key documentation improves developer onboarding. Technologies involved: JavaScript/TypeScript, WebExtensions APIs, cross-repo collaboration, and lint/code-review discipline.
February 2026: Delivered two key items across MDN repositories, enhancing developer experience around the Permissions API and expanding browser compatibility for data collection permissions. The work emphasizes clear API usage, practical examples, and broader extension support, supported by cross-repo collaboration and precise commits.
February 2026: Delivered two key items across MDN repositories, enhancing developer experience around the Permissions API and expanding browser compatibility for data collection permissions. The work emphasizes clear API usage, practical examples, and broader extension support, supported by cross-repo collaboration and precise commits.
January 2026 monthly summary focusing on delivering features and stabilizing developer tooling across browser compatibility data and content workstreams. Highlights include enabling localhost access for MV3 add-ons, introducing MASQUE proxy support for the proxy API, enhancing web extensions development/docs, and advancing Clipboard API usability with a new Paste button and updated cross-browser guidance.
January 2026 monthly summary focusing on delivering features and stabilizing developer tooling across browser compatibility data and content workstreams. Highlights include enabling localhost access for MV3 add-ons, introducing MASQUE proxy support for the proxy API, enhancing web extensions development/docs, and advancing Clipboard API usability with a new Paste button and updated cross-browser guidance.
December 2025 highlights: Delivered cross-repo API and documentation improvements across MDN content and browser-compat data, prioritizing developer clarity, cross-browser consistency, and extension capabilities. Key outcomes include enhanced documentation for URL match patterns, cross-browser WebExtensions API compatibility updates, Firefox-specific WebNavigation improvements, MASQUE-enabled Proxy API enhancements with cross-browser notes, and clarified Clipboard API permissions and user gesture considerations. These efforts reduce integration risk, accelerate extension development, and improve platform reliability for web developers and extension authors.
December 2025 highlights: Delivered cross-repo API and documentation improvements across MDN content and browser-compat data, prioritizing developer clarity, cross-browser consistency, and extension capabilities. Key outcomes include enhanced documentation for URL match patterns, cross-browser WebExtensions API compatibility updates, Firefox-specific WebNavigation improvements, MASQUE-enabled Proxy API enhancements with cross-browser notes, and clarified Clipboard API permissions and user gesture considerations. These efforts reduce integration risk, accelerate extension development, and improve platform reliability for web developers and extension authors.
November 2025 monthly summary focusing on delivering robust privacy controls, cross-browser storage improvements, and developer-facing documentation enhancements across two MDN repos. Key outcomes include 1) new data privacy and storage API capabilities with manifest permissions keys and clarified sessionStorage semantics, 2) Android-specific sync storage support to enable user data synchronization via Mozilla accounts, and 3) updated and clarified documentation for data collection permissions and browsingData API usage to improve developer onboarding and compliance.
November 2025 monthly summary focusing on delivering robust privacy controls, cross-browser storage improvements, and developer-facing documentation enhancements across two MDN repos. Key outcomes include 1) new data privacy and storage API capabilities with manifest permissions keys and clarified sessionStorage semantics, 2) Android-specific sync storage support to enable user data synchronization via Mozilla accounts, and 3) updated and clarified documentation for data collection permissions and browsingData API usage to improve developer onboarding and compliance.
October 2025 monthly summary focusing on deliverables and business value for two MDN repositories. Major outcomes include comprehensive WebExtensions API documentation improvements, cross-context storage usage reporting enhancements, and bug fixes that improve developer experience and cross-browser consistency.
October 2025 monthly summary focusing on deliverables and business value for two MDN repositories. Major outcomes include comprehensive WebExtensions API documentation improvements, cross-context storage usage reporting enhancements, and bug fixes that improve developer experience and cross-browser consistency.
September 2025 focused on delivering cross-browser WebExtensions parity and improving developer UX across the MDN ecosystem. We implemented API and data model enhancements, integrated UI improvements, and hardened cross-browser behavior with targeted fixes and documentation updates.
September 2025 focused on delivering cross-browser WebExtensions parity and improving developer UX across the MDN ecosystem. We implemented API and data model enhancements, integrated UI improvements, and hardened cross-browser behavior with targeted fixes and documentation updates.
August 2025 monthly summary: Implemented and documented key WebExtensions API improvements across MDN repositories, delivering a new StorageArea.getKeys() API, onUserSettingsChanged event support, and comprehensive cross-browser documentation updates to improve developer productivity and consistency.
August 2025 monthly summary: Implemented and documented key WebExtensions API improvements across MDN repositories, delivering a new StorageArea.getKeys() API, onUserSettingsChanged event support, and comprehensive cross-browser documentation updates to improve developer productivity and consistency.
July 2025 focused on data integrity and API robustness for WebExtensions, delivering critical fixes and documentation improvements across two MDN repositories. Key outcomes include corrected compatibility data, more reliable Downloads API behavior, upfront cookie validation groundwork for WebExtensions, and clearer Chrome-specific WebNavigation documentation, collectively enhancing reliability, security, and developer experience.
July 2025 focused on data integrity and API robustness for WebExtensions, delivering critical fixes and documentation improvements across two MDN repositories. Key outcomes include corrected compatibility data, more reliable Downloads API behavior, upfront cookie validation groundwork for WebExtensions, and clearer Chrome-specific WebNavigation documentation, collectively enhancing reliability, security, and developer experience.
June 2025 performance summary focusing on delivering high-impact browser compatibility data, expanding extension APIs, and improving developer documentation across two MDN repositories. The work emphasizes business value for developers integrating with browser data and i18n features, as well as better UX through documentation.
June 2025 performance summary focusing on delivering high-impact browser compatibility data, expanding extension APIs, and improving developer documentation across two MDN repositories. The work emphasizes business value for developers integrating with browser data and i18n features, as well as better UX through documentation.
May 2025 monthly summary: Focused on expanding WebExtensions coverage in MDN by introducing compatibility data for the Tab Groups API, stabilizing tabGroups behavior, and delivering comprehensive documentation updates to improve developer onboarding and cross-browser consistency. This work improves developer confidence, accelerates adoption of the Tab Groups API, and clarifies API behavior across updates.
May 2025 monthly summary: Focused on expanding WebExtensions coverage in MDN by introducing compatibility data for the Tab Groups API, stabilizing tabGroups behavior, and delivering comprehensive documentation updates to improve developer onboarding and cross-browser consistency. This work improves developer confidence, accelerates adoption of the Tab Groups API, and clarifies API behavior across updates.
April 2025 highlights: Delivered critical enhancements to the MDN browser-compat-data and content repositories that improve cross-browser compatibility, data accuracy, and developer experience. Key feature work includes implementing tab.group and tab.ungroup with groupId and updating onUpdate.filter.properties to reflect grouping; expanding Chrome browsingData.RemovalOptions with new properties to align with evolving data removal capabilities; and advancing WebRequest compatibility data by implementing handlerBehaviorChanged (pre-138) and adding Safari 18 MV3 support, while tightening accuracy of non-functional API details. Documentation efforts synthesized into a comprehensive WebExtensions guide covering tab grouping, localization, removal options, manifest key compatibility, author behavior across browsers, and Safari background/page handling. Major bug fixes include correcting attribution for getUserSettings to browserAction and ensuring extension context menus persist across restarts when using non-persistent background scripts. Overall impact: strengthened cross‑browser data quality, clearer developer guidance, reduced integration risk, and broader Safari MV3 support. Technologies demonstrated: WebExtensions API coverage, MV3 considerations, cross‑browser data modeling, release-note discipline, documentation design, and collaboration across MDN teams.
April 2025 highlights: Delivered critical enhancements to the MDN browser-compat-data and content repositories that improve cross-browser compatibility, data accuracy, and developer experience. Key feature work includes implementing tab.group and tab.ungroup with groupId and updating onUpdate.filter.properties to reflect grouping; expanding Chrome browsingData.RemovalOptions with new properties to align with evolving data removal capabilities; and advancing WebRequest compatibility data by implementing handlerBehaviorChanged (pre-138) and adding Safari 18 MV3 support, while tightening accuracy of non-functional API details. Documentation efforts synthesized into a comprehensive WebExtensions guide covering tab grouping, localization, removal options, manifest key compatibility, author behavior across browsers, and Safari background/page handling. Major bug fixes include correcting attribution for getUserSettings to browserAction and ensuring extension context menus persist across restarts when using non-persistent background scripts. Overall impact: strengthened cross‑browser data quality, clearer developer guidance, reduced integration risk, and broader Safari MV3 support. Technologies demonstrated: WebExtensions API coverage, MV3 considerations, cross‑browser data modeling, release-note discipline, documentation design, and collaboration across MDN teams.
March 2025 monthly summary: Strengthened WebExtensions developer experience and cross‑browser compatibility across mdn/content and mdn/browser-compat-data. Key deliverables include consolidated documentation and release notes for the WebExtensions API, manifest.json enhancements, and MV3 alignment efforts, along with targeted fixes to align with Firefox version requirements. Notable reliability improvements and risk mitigations were addressed to support smoother releases and onboarding.
March 2025 monthly summary: Strengthened WebExtensions developer experience and cross‑browser compatibility across mdn/content and mdn/browser-compat-data. Key deliverables include consolidated documentation and release notes for the WebExtensions API, manifest.json enhancements, and MV3 alignment efforts, along with targeted fixes to align with Firefox version requirements. Notable reliability improvements and risk mitigations were addressed to support smoother releases and onboarding.
February 2025 performance summary for the MDN content repositories (mdn/content, mdn/browser-compat-data). Focused on delivering developer-facing features, clarifying API behavior, and solidifying cross-repo compatibility data to accelerate extension development and browser support decisions. Key outcomes include: - Key features delivered: Introduced the userScripts API in mdn/content with accompanying documentation and legacy content migration; completed extensive WebExtensions API documentation improvements (TAB_ID_NONE, content script persistence, F13–F19 key support, onMessageExternal async handling, managed storage behavior, sidePanel compatibility, web_accessible_resources, release notes, shortcut commands, and API type descriptions). - Cross-repo compatibility data: Added and reconciled WebExtension.userScripts compatibility data across mdn/content and mdn/browser-compat-data, including runtime notes, MV3 cross-references, and platform clarifications (Firefox for Android). - New commands/docs in browser-compat-data: Added commands.openShortcutSettings data to support shortcut configuration UX, along with related documentation for openShortcutSetting command concepts. - Major fixes and clarifications: Addressed documentation and policy clarifications including managed storage policy, web_accessible_resources matching, storage quota enforcement release notes, and openShortcutSetting documentation. - Overall impact: Enhanced developer experience with clear API guidance, improved cross-browser compatibility, and better onboarding for extension developers, reducing support overhead and accelerating ship readiness. - Technologies/skills demonstrated: API design and documentation, cross-repo collaboration, compatibility data curation, release notes and changelog discipline, and platform considerations (WebExtensions, MV3, Firefox variants).
February 2025 performance summary for the MDN content repositories (mdn/content, mdn/browser-compat-data). Focused on delivering developer-facing features, clarifying API behavior, and solidifying cross-repo compatibility data to accelerate extension development and browser support decisions. Key outcomes include: - Key features delivered: Introduced the userScripts API in mdn/content with accompanying documentation and legacy content migration; completed extensive WebExtensions API documentation improvements (TAB_ID_NONE, content script persistence, F13–F19 key support, onMessageExternal async handling, managed storage behavior, sidePanel compatibility, web_accessible_resources, release notes, shortcut commands, and API type descriptions). - Cross-repo compatibility data: Added and reconciled WebExtension.userScripts compatibility data across mdn/content and mdn/browser-compat-data, including runtime notes, MV3 cross-references, and platform clarifications (Firefox for Android). - New commands/docs in browser-compat-data: Added commands.openShortcutSettings data to support shortcut configuration UX, along with related documentation for openShortcutSetting command concepts. - Major fixes and clarifications: Addressed documentation and policy clarifications including managed storage policy, web_accessible_resources matching, storage quota enforcement release notes, and openShortcutSetting documentation. - Overall impact: Enhanced developer experience with clear API guidance, improved cross-browser compatibility, and better onboarding for extension developers, reducing support overhead and accelerating ship readiness. - Technologies/skills demonstrated: API design and documentation, cross-repo collaboration, compatibility data curation, release notes and changelog discipline, and platform considerations (WebExtensions, MV3, Firefox variants).
January 2025 focused on delivering precise data enhancements and robust UI/documentation improvements to the MDN repositories. Key outcomes include feature work to improve browser compatibility data and bug fixes that increase reliability and developer confidence, with cross-repo documentation refinements. Key features delivered: - Browser-compat-data: Developer Tools Panels metadata completed with JSON updates and MDN URLs (commit 182193b8fe44bdd56e362c194cfd19898f2c1a12). - Browser-compat-data: Added details field support for webRequest API compatibility data (commit 7e79e7bbc39c06da4242d75cfa346e5053fddea7). Major bugs fixed: - mdn/content: Ensure menus.update and menus.remove return an error when the specified menu item does not exist (commit 11611c3ed37642bde343608b6e69cb177cf54fa2). - Documentation refinements: Firefox InterruptReason notes and Menu UI error handling updates (commits 312f3edcab23d699e1eb59a9ee7911cdf75472ea and 6b05bed5493dc667250124004350861fa38b0d8a). Overall impact and accomplishments: - Increased data accuracy and completeness for developers relying on cross-browser compatibility data. - Reduced risk of silent UI failures and clarified error signaling for downloads and menus. - Improved developer experience through targeted documentation improvements and clearer behavior expectations across repositories. Technologies/skills demonstrated: - Data modeling and schema evolution (details field) and data integrity across JSON data for web APIs. - Cross-repo coordination, commit traceability, and documentation governance. - QA-driven documentation refinements and user-facing behavior validation.
January 2025 focused on delivering precise data enhancements and robust UI/documentation improvements to the MDN repositories. Key outcomes include feature work to improve browser compatibility data and bug fixes that increase reliability and developer confidence, with cross-repo documentation refinements. Key features delivered: - Browser-compat-data: Developer Tools Panels metadata completed with JSON updates and MDN URLs (commit 182193b8fe44bdd56e362c194cfd19898f2c1a12). - Browser-compat-data: Added details field support for webRequest API compatibility data (commit 7e79e7bbc39c06da4242d75cfa346e5053fddea7). Major bugs fixed: - mdn/content: Ensure menus.update and menus.remove return an error when the specified menu item does not exist (commit 11611c3ed37642bde343608b6e69cb177cf54fa2). - Documentation refinements: Firefox InterruptReason notes and Menu UI error handling updates (commits 312f3edcab23d699e1eb59a9ee7911cdf75472ea and 6b05bed5493dc667250124004350861fa38b0d8a). Overall impact and accomplishments: - Increased data accuracy and completeness for developers relying on cross-browser compatibility data. - Reduced risk of silent UI failures and clarified error signaling for downloads and menus. - Improved developer experience through targeted documentation improvements and clearer behavior expectations across repositories. Technologies/skills demonstrated: - Data modeling and schema evolution (details field) and data integrity across JSON data for web APIs. - Cross-repo coordination, commit traceability, and documentation governance. - QA-driven documentation refinements and user-facing behavior validation.
Month: 2024-12 — Focused on stabilizing content scripting reliability, clarifying optional permissions, and aligning MDN data with latest browser changes. Delivered a set of high-impact, well-scoped fixes and a documentation enhancement across two repositories.
Month: 2024-12 — Focused on stabilizing content scripting reliability, clarifying optional permissions, and aligning MDN data with latest browser changes. Delivered a set of high-impact, well-scoped fixes and a documentation enhancement across two repositories.
Monthly work summary for 2024-11 focusing on MDN content and MDN browser-compat-data repos. Highlights include feature delivery, critical bug fixes, cross-repo improvements, and documentation work that enhances interoperability, developer experience, and data quality.
Monthly work summary for 2024-11 focusing on MDN content and MDN browser-compat-data repos. Highlights include feature delivery, critical bug fixes, cross-repo improvements, and documentation work that enhances interoperability, developer experience, and data quality.
October 2024: Focused on clarifying WebExtensions content script capabilities and aligning cross-browser storage schema. Delivered precise docs and schema updates across two MDN repos, reducing developer confusion and improving cross-browser consistency and maintainability. Specific outcomes include a cross-domain XHR clarification for content scripts and Firefox impl_url support for manifest.storage.managed_schema.
October 2024: Focused on clarifying WebExtensions content script capabilities and aligning cross-browser storage schema. Delivered precise docs and schema updates across two MDN repos, reducing developer confusion and improving cross-browser consistency and maintainability. Specific outcomes include a cross-domain XHR clarification for content scripts and Firefox impl_url support for manifest.storage.managed_schema.

Overview of all repositories you've contributed to across your timeline