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+# Changelog
+
+All notable changes to `hed-validator` will be documented in this file.
+
+<!-- scriv-insert-here -->
+
+<a id='changelog-4.2.0'></a>
+## 4.2.0 — 2026-05-11
+
+### Added
+
+- `BidsWebAccessor` — a new browser-compatible BIDS file accessor that reads
+  dataset files from browser `File` objects provided via an
+  `<input webkitdirectory>` element or drag-and-drop upload. Schema loading is
+  performed via remote HTTPS fetching. This enables in-browser BIDS/HED
+  validation without a server. ([#718])
+
+- Tests for `BidsWebAccessor` covering core accessor behavior. ([#718])
+
+- The main package is now fully browser-friendly via its ESM build
+  (`dist/esm/index.js`). The `exports` map exposes both `browser` and
+  `import` conditions pointing to the ESM bundle. ([#719])
+
+### Changed
+
+- The browser UI application (`browser/`) has been removed from this package
+  and moved to a dedicated repository:
+  [hed-standard/hed-web](https://github.com/hed-standard/hed-web). ([#721])
+
+- CI GitHub Actions: the `deploy-pages` workflow now deploys documentation
+  only; browser app build steps have been removed. ([#720])
+
+- Bundling refactored for better ESM/browser compatibility (stage 1). ([#719])
+
+- `ts-jest` removed from dev dependencies; TypeScript upgraded to 6.0.2, then
+  6.0.3. ([#697])
+
+- `tsconfig.json` handling revised to address TypeScript 6.x deprecations. ([#692])
+
+- README updated to reflect separation of browser interface into `hed-web`. ([#721])
+
+### Fixed
+
+- Picomatch security vulnerability addressed. ([#692])
+
+- CI workflow permissions tightened to reduce attack surface. ([#692])
+
+### Dependencies
+
+- `fast-xml-parser` updated through 5.5.8 → 5.7.2
+- `eslint` updated through 10.1.0 → 10.3.0
+- `@babel/preset-env` updated 7.29.0 → 7.29.3
+- `@babel/plugin-transform-modules-systemjs` updated
+- `globals` updated 17.4.0 → 17.6.0
+- `prettier` updated 3.8.1 → 3.8.3
+- `typedoc` updated 0.28.18 → 0.28.19
+- `@types/node` updated 25.5.0 → 25.6.0
+- `typescript` updated 6.0.2 → 6.0.3
+- `actions/deploy-pages` updated 4 → 5
+- `actions/upload-pages-artifact` updated 4 → 5
+
+[#692]: https://github.com/hed-standard/hed-javascript/pull/692
+[#697]: https://github.com/hed-standard/hed-javascript/pull/697
+[#718]: https://github.com/hed-standard/hed-javascript/pull/718
+[#719]: https://github.com/hed-standard/hed-javascript/pull/719
+[#720]: https://github.com/hed-standard/hed-javascript/pull/720
+[#721]: https://github.com/hed-standard/hed-javascript/pull/721
+
+---
+
+<a id='changelog-4.1.4'></a>
+## 4.1.4 — 2025-08-11
+
+- Package repository URL shortened to short form in `package.json`.
+- Type test infrastructure: added Unix shell script for running type tests
+  locally; switched to standard Bourne shell.
+- ESM build configurations merged.
+
+---
+
+<a id='changelog-4.1.3'></a>
+## 4.1.3 — 2025-08-11
+
+- Updated test configuration to be compatible with Node 22.
+
+---
+
+<a id='changelog-4.1.2'></a>
+## 4.1.2 — 2025-08-09
+
+- Replaced `xml2js` with `fast-xml-parser`.
+- Switched from `cross-fetch` to Node's internal `fetch` (requires Node ≥ 22).
+
+---
+
+<a id='changelog-4.1.1'></a>
+## 4.1.1 — 2025-08-07
+
+- Fixed type declaration issues from 4.1.0 release.
+
+---
+
+<a id='changelog-4.1.0'></a>
+## 4.1.0 — 2025-08-05
+
+- Added `types/index.d.ts` — full TypeScript type declarations for the public API.
+- Added scripts for local type testing (`scripts/test-types-local*.{js,sh,ps1}`).
+- Upgraded to Jest 30.
+
+---
+
+<a id='changelog-4.0.1'></a>
+## 4.0.1 — 2025-03-17
+
+- Recursive attribute processing refactored.
+- Upgraded esbuild, eslint, typedoc.
+
+---
+
+<a id='changelog-4.0.0'></a>
+## 4.0.0 — 2025-03-08
+
+Major rewrite. Key changes:
+- Full ESM module structure.
+- New BIDS integration layer: `BidsDataset`, `BidsTsvFile`, `BidsJsonFile`,
+  `BidsSidecar`, `BidsHedIssue`, `buildBidsSchemas`.
+- Browser-compatible build via esbuild (`dist/esm/`, `dist/commonjs/`).
+- Replaced `xml2js` dependency pipeline with `fast-xml-parser`.
+- Removed `date-and-time` and `path` runtime dependencies.