Plugins can be installed from `.jpl` files in the [web build](https://app.joplincloud.com/) of the mobile app. This can help with mobile plugin development in a few ways:
- Eliminates the need to transfer the plugin's built `.jpl` file to an Android device after every change.
- It may be easier to inspect running plugins from a browser's development tools.
To install a custom plugin on web,
1. Build your plugin (run `npm run dist` from the plugin's directory).
2. Open [web build](https://app.joplincloud.com/) of Joplin mobile.
3. Go to "Configuration" > "Plugins" > "Enable plugin support" > "Advanced".
4. Click "Install from file".
5. Navigate to the base directory of your plugin.
6. Open the `publish/` folder.
7. Select the `.jpl` file.
Your plugin should now be loaded!
:::note
If you encounter an "incompatible with Joplin mobile" error, be sure that `"platforms": ["mobile", "desktop"]` is included in your plugin's `manifest.json` ([documentation](./plugin_manifest.md)).
:::
After loading, plugins are run in an `<iframe>` with an `about:srcdoc` URL. To view the plugin's console output and interact with global plugin variables (e.g. `joplin.commands`),
1. Open your browser's development tools.
- On most desktop browsers, this can be done by pressing <kbd>F12</kbd>.
- The following steps were tested on Firefox, Chrome, and Safari desktop.
2. Click on the "Console" tab.
3. To run JavaScript in the context of your plugin, [select its JavaScript context](https://developer.chrome.com/docs/devtools/console/reference#context).
- The JavaScript context will be named `about:srcdoc`.
- If using Chrome's DevTools, the [`debug`](https://developer.chrome.com/docs/devtools/console/utilities#debug-function) and other console utility function may be helpful.
## Android: Inspecting a WebView
On mobile, all plugins run in `iframe`s within a `WebView`.
On Android, it's possible to inspect this `WebView` with Google Chrome's development tools. To do this,
