Offline Mode
ElectroBoard is a Progressive Web App (PWA), so it can work without an internet connection after the first visit.
How It Works
On your first visit, the Service Worker caches the application shell and static assets (HTML, CSS, JavaScript, fonts, icons). After that:
- The app loads from cache
- Projects open from the browser's local storage (localStorage)
- All edits are saved locally in real time
If you try to open a page that was not cached yet (for example, the first attempt to open the site with no network), you will see an offline page with a "Try again" button.
Sync When Back Online
ElectroBoard uses a dual-write system: every save is written at the same time to the browser's local storage and to the cloud database (Supabase). While you are offline, changes stay in local storage and the toolbar indicator may show 🔴 (no cloud connection).
When the connection is restored, local changes are uploaded to the cloud automatically. If a conflict is detected (the same project was edited on another device), ElectroBoard does not overwrite your changes silently — you choose which version to keep.
⚠️ Warning: if you clear your browser data (local storage) before syncing, changes not yet saved to the cloud will be lost.
What Works Offline
| Feature | Offline? |
|---|---|
| Open existing projects | Yes |
| Edit panel, add devices | Yes |
| Undo/Redo | Yes |
| Export to PDF | Yes |
| Generate SLD | Yes |
| Create new project | Yes |
| Share via link | No (requires internet) |
| Cloud sync | No (queued, synced on reconnect) |
| AI Consultant | No (requires internet) |
Saving to a File
For guaranteed offline portability, use Export > Save as file to download a .eboard file.
Board Data Safety
ElectroBoard protects your projects in two edge cases. When either happens, a warning bar appears at the top of the editor:
Board saved by a newer app version. If you open a board saved by a newer version of ElectroBoard (for example, synced from another device that already updated), it opens read-only. You can still inspect and copy values, but changes won't be saved — so an older build can't overwrite the newer format. An "Update the app" button pulls the latest version right away; once updated, the board becomes editable again.
Corrupted board data. If the saved data can't be read, ElectroBoard doesn't lose it silently: it keeps a backup copy of the corrupted data and opens a fresh board. A "Discard & start fresh" button confirms the action and re-enables saving. If the backup couldn't be written (for example, storage is full), a separate line tells you so.
First-Time Setup
Offline mode activates after the first online visit. The Service Worker caches the app automatically in the background.