## Move editor under `frontend/editor/`
Pure restructure: `frontend/` becomes the workspace, `frontend/editor/`
holds
the PDF editor. 1775 file renames + 40 wiring edits. No logic changes.
### Why
`frontend/` is currently the editor — its `src/`, `public/`,
`src-tauri/`,
config files all sit at the root. Promoting `frontend/` to a
workspace and putting the editor in a sibling folder leaves room for
future
apps to drop in alongside it, sharing one `package.json` /
`node_modules` /
lint config / Storybook.
### What moves
frontend/
├── editor/ ← NEW: everything editor-specific
│ ├── src/ ← was frontend/src/
│ ├── public/ ← was frontend/public/
│ ├── src-tauri/ ← was frontend/src-tauri/
│ ├── index.html, vite.config.ts, vitest.config.ts, playwright.config.ts
│ ├── tsconfig*.json, tailwind.config.js, postcss.config.js
│ ├── scripts/
│ ├── .env, .env.desktop, .env.saas
│ └── DeveloperGuide.md
├── package.json, package-lock.json, node_modules/ ← workspace install
├── eslint.config.mjs, .prettierrc, .prettierignore ← shared tooling
├── .gitignore
└── README.md
### Wiring edits (40 files)
- `.taskfiles/frontend.yml`, `desktop.yml`, `e2e.yml`
- `build.gradle`, `app/core/build.gradle`
- `eslint.config.mjs`, `frontend/package.json`, `.gitignore`,
`.prettierignore`
- `docker/frontend/Dockerfile`
- 8 `.github/workflows/*.yml`, plus `.github/dependabot.yml`,
`.github/config/.files.yaml`, `.github/labeler-config-srvaroa.yml`
- `scripts/translations/**`
- Docs: `AGENTS.md`, `CLAUDE.md`, `ADDING_TOOLS.md`,
`DeveloperGuide.md`,
`WINDOWS_SIGNING.md`, `devGuide/HowToAddNewLanguage.md`,
`frontend/README.md`,
`frontend/editor/DeveloperGuide.md`
Plus 3 renamed + edited: `editor/vite.config.ts` (env path +
node_modules
walk-up), `editor/scripts/setup-env.mts` (renamed from `.ts` for
`import.meta.url`), `editor/scripts/build-provisioner.mjs` (resolve
src-tauri
relative to script).
### Verification
| Check | Result |
|---|---|
| `task frontend:typecheck:all` (6 variants) | exit 0 |
| `task frontend:lint` (eslint + dpdm) | exit 0 |
| `task frontend:format:check` | exit 0 |
| `task frontend:test` | 657 tests pass, 50 files |
| `task frontend:build:{core,proprietary,saas,desktop,prototypes}` | all
green |
| `task desktop:build` | full Tauri pipeline →
`Stirling-PDF_2.11.0_x64_en-US.msi` |
| `playwright test --list --project=stubbed` | 172 tests discovered |
`task desktop:build` exercises the heaviest path — Rust + WiX + MSI
bundle
against the moved `editor/src-tauri/`. If anything in the restructure
was
wrong it wouldn't have built.
### Test plan
- [ ] `frontend-validation.yml` green
- [ ] `e2e-stubbed.yml` green
- [ ] `tauri-build.yml` green on at least one platform
- [ ] `check_toml.yml` runs on a translation-touching PR
---------
Co-authored-by: Claude Opus 4.7 (1M context) <[email protected]>
Windows PDF Thumbnail Handler
A lightweight COM DLL that provides PDF page-preview thumbnails in Windows Explorer when Stirling-PDF is the default PDF application.
Why this exists
When Stirling-PDF registers as the default PDF handler, Windows associates .pdf files with Stirling's ProgID. Without a thumbnail handler on that ProgID, Explorer falls back to showing the application icon (the big S logo) instead of a page preview. This DLL restores thumbnail previews by implementing the Windows Shell IThumbnailProvider COM interface.
How it works
- Explorer requests a thumbnail — when a folder with PDFs is opened in Medium/Large icon view, Explorer loads the DLL via the registered COM CLSID.
- Shell calls
IInitializeWithStream— passes the PDF file content as anIStream. - Shell calls
IThumbnailProvider::GetThumbnail(cx)— requests a bitmap of sizecx × cx. - The DLL renders page 1 using the built-in
Windows.Data.PdfWinRT API (the same engine Edge uses), preserving aspect ratio. - WIC decodes the rendered PNG into BGRA pixels, which are copied into an
HBITMAPviaCreateDIBSection. - Explorer displays the bitmap as the file's thumbnail.
All COM methods are wrapped in catch_unwind so a malformed PDF cannot crash Explorer.
Technical details
| Language | Rust (cdylib) |
| DLL size | ~156 KB |
| External deps | None — uses only Windows built-in APIs |
| PDF renderer | Windows.Data.Pdf (WinRT, Windows 10+) |
| Image decode | WIC (IWICImagingFactory) with BGRA32 format conversion |
| COM CLSID | {2D2FBE3A-9A88-4308-A52E-7EF63CA7CF48} |
| Threading model | Apartment (STA — standard for shell extensions) |
| Min Windows | Windows 10 |
Registry entries (managed by MSI)
The WiX installer (provisioning.wxs) registers:
- CLSID at
HKLM\SOFTWARE\Classes\CLSID\{2D2FBE3A-...}\InprocServer32pointing to the DLL - Shellex at
HKLM\SOFTWARE\Classes\.pdf\shellex\{E357FCCD-...}linking.pdfthumbnails to our CLSID
Both are automatically removed on uninstall.
Building
The DLL is built automatically as part of the Tauri build pipeline via build-provisioner.mjs:
cd frontend
npm run tauri-build
To build the DLL standalone:
cd frontend/src-tauri/thumbnail-handler
cargo build --release
# Output: target/release/stirling_thumbnail_handler.dll
Linux / macOS
This DLL is Windows-only. Linux and macOS don't need it — their thumbnail systems (thumbnailers on Linux, Quick Look on macOS) are decoupled from the default app association and continue working regardless of which app is set as default.