docs: correct the development and logging pages against the Vite proxy, the build config and the JSON log formatters

docs/getting-started/advanced-topics/development.md

@@ -40,7 +40,7 @@ Testing it and reporting what you find is the lowest-effort way to help, and it
 | Requirement | Version |
 |-------------|---------|
 | **Python** | 3.11 or 3.12 (see note below; 3.13 not supported yet) |
-| **Node.js** | 22.10+ |
+| **Node.js** | 20.19+ on Node 20, or 22.13+ on Node 22 (`package.json` stops at 22.x; with `engine-strict` on, locked dependencies such as `pdfjs-dist`, `yargs` and `eslint-visitor-keys` need 20.19 or later, and `eslint-visitor-keys` needs 22.13 or later on Node 22; the official image builds on Node 22) |
 | **Git** | Any recent version |
 
 :::info Python version compatibility
@@ -79,7 +79,7 @@ npm run build
 npm run dev
 ```
 
-`npm run build` compiles the frontend and catches build-time errors early. `npm run dev` then starts the dev server at [http://localhost:5173](http://localhost:5173). It will show a waiting screen until the backend is running.
+`npm run build` compiles the frontend and catches build-time errors early. `npm run dev` then starts the dev server at [http://localhost:5173](http://localhost:5173). Until the backend is running it redirects to a "Backend Required" error page; reload once the backend is up.
 
 :::tip
 If `npm install` fails with compatibility warnings, run `npm install --force`.
@@ -114,7 +114,7 @@ pip install -r requirements.txt -U
 sh dev.sh
 ```
 
-The backend starts at [http://localhost:8080](http://localhost:8080). API docs are available at [http://localhost:8080/docs](http://localhost:8080/docs).
+`dev.sh` does not generate a secret key, so export `WEBUI_SECRET_KEY` (any long random value) or add it to the root `.env` before running it; without it the backend stops at startup. The backend starts at [http://localhost:8080](http://localhost:8080). API docs are available at [http://localhost:8080/docs](http://localhost:8080/docs). The `/docs` page is served only when `ENV=dev`, which is the default when running from source; the Docker image runs with `ENV=prod` and does not serve it.
 
 Refresh the frontend at [http://localhost:5173](http://localhost:5173) and you should see the full application.
 
@@ -133,6 +133,8 @@ export CORS_ALLOW_ORIGIN="http://localhost:5173;http://localhost:8080;http://192
 
 3. Restart the backend and browse to `http://192.168.1.42:5173`
 
+`npm run dev` runs `vite dev --host`, so the dev server already listens on every interface and proxies `/api`, `/ollama`, `/openai`, `/oauth` and `/ws` to the backend. The CORS entry is still needed because Socket.IO checks the browser's `Origin` against `CORS_ALLOW_ORIGIN`, and the proxy passes that header through. If the backend runs on another machine, point the proxy at it with `WEBUI_BACKEND_URL=http://<host>:8080 npm run dev`.
+
 ---
 
 ## Troubleshooting
@@ -160,11 +162,11 @@ lsof -i :5173
 Get-Process -Id (Get-NetTCPConnection -LocalPort 5173).OwningProcess
 ```
 
-Terminate the process or change the port in `vite.config.js` (frontend) or `dev.sh` (backend).
+Terminate the process, or start on another port: `PORT=9000 sh dev.sh` for the backend (then `WEBUI_BACKEND_URL=http://localhost:9000 npm run dev`), and `npm run dev:5050` for the frontend after adding `http://localhost:5050` to `CORS_ALLOW_ORIGIN` in `backend/dev.sh`.
 
-### Icons not loading (CORS)
+### Icons not loading
 
-If static assets fail to load, configure `CORS_ALLOW_ORIGIN` in `backend/dev.sh` to include your frontend URL. See [CORS configuration](/reference/env-configuration#cors_allow_origin) for details.
+Static assets come from the Vite dev server, not the backend, so `CORS_ALLOW_ORIGIN` does not affect them. Check the dev server's terminal for the failing request instead.
 
 ### Hot reload not working
 

docs/getting-started/advanced-topics/logging.md

@@ -13,7 +13,7 @@ Open WebUI has two logging surfaces: the **browser console** for frontend debugg
 
 ## Frontend Logging
 
-The frontend uses standard browser `console.log()` calls. Open your browser's developer tools (**F12** or **Cmd+Option+I** on macOS), navigate to the **Console** tab, and you'll see informational messages, warnings, and errors from the client application.
+The frontend logs to the browser console: open your browser's developer tools (**F12** or **Cmd+Option+I** on macOS) and go to the **Console** tab. Production builds, the Docker image included, strip `console.log`, `console.debug` and `console.error` calls at build time unless the frontend was built with `ENV=dev`, so there you mainly see `console.warn` and `console.info` output plus the browser's own errors; run the dev server (`npm run dev`) for the full output.
 
 Browser-specific documentation:
 
@@ -60,6 +60,8 @@ environment:
 Use `DEBUG` for development and troubleshooting. For production, stick with `INFO` or `WARNING` to keep log volume manageable.
 :::
 
+A value Python's `logging` module does not recognise (for example `TRACE`) falls back to `INFO`. Use one of the level names above; aliases such as `WARN` or `FATAL` are not Loguru level names. The per-component `SRC_LOG_LEVELS` mechanism from older releases is kept only as an empty placeholder and no longer changes any logger.
+
 ---
 
 ### What the Log Level Costs
@@ -94,8 +96,8 @@ environment:
 | `msg` | Log message |
 | `caller` | Source location (`module:function:line`) |
 | `extra` | Additional context data (if any) |
-| `error` | Error details (if applicable) |
-| `stacktrace` | Stack trace (if applicable) |
+| `error` | Error details, as an object with `type`, `message` and `stacktrace` (if applicable) |
+| `stacktrace` | Only on lines logged before the Loguru sink starts by a call that passes `stack_info=True` (Open WebUI itself does not); those early lines carry `caller` as the module name alone and `error` as a plain string |
 
 **Example output:**