@capgo/capacitor-webview-guardian

Bring your Capacitor app back to life when the OS kills its WebView in the background: Webview Guardian checks the renderer on foreground and reloads it automatically.

🤖 Building with an AI coding agent? Install Capgo skills so Claude Code, Codex, Cursor, Copilot, or Gemini CLI know how to install and use @capgo/capacitor-webview-guardian in your Capacitor app: npx skills add Cap-go/capgo-skills. Then ask your agent: "Add @capgo/capacitor-webview-guardian to my Capacitor app and wire it up." Agent setup guides · Hosted MCP

Key features

• Monitoring: startMonitoring() and stopMonitoring() watch foreground events.
• Auto restart: reloads a terminated WebView with a reload, reloadFromOrigin or customUrl strategy.
• Health probe: checkNow() tests the WebView right away.
• State and events: getState() and the foreground event.
• Platforms: iOS and Android. Not available on web.

Keep your Capacitor app alive after the OS kills its WebView while the app is in the background. Webview Guardian listens for foreground events, probes the renderer, and reloads it automatically (or notifies you so you can recover your own state) when the render process was terminated.

Compatibility

Note: The major version of this plugin follows the major version of Capacitor. Use the version that matches your Capacitor installation (e.g., plugin v8 for Capacitor 8). Only the latest major version is actively maintained.

Install

You can use our AI-Assisted Setup to install the plugin. Add the Capgo skills to your AI tool using the following command:

npx skills add https://github.com/cap-go/capacitor-skills --skill capacitor-plugins

Then use the following prompt:

Use the `capacitor-plugins` skill from `cap-go/capacitor-skills` to install the `@capgo/capacitor-webview-guardian` plugin in my project.

If you prefer Manual Setup, install the plugin by running the following commands and follow the platform-specific instructions below:

npm install @capgo/capacitor-webview-guardian
npx cap sync

Usage

import { WebviewGuardian } from '@capgo/capacitor-webview-guardian';

await WebviewGuardian.startMonitoring({
  foregroundDebounceMs: 800,
  autoRestart: true,
  restartStrategy: 'reload',
});

WebviewGuardian.addListener('webviewRestarted', ({ reason }) => {
  console.info('[guardian] WebView restarted', reason);
});

API

• startMonitoring(...)
• stopMonitoring()
• getState()
• checkNow(...)
• addListener('foreground' | 'webviewHealthy' | 'webviewCrashed' | 'webviewRestarted', ...)
• Interfaces
• Type Aliases

startMonitoring(...)

startMonitoring(options?: StartMonitoringOptions | undefined) => Promise<GuardianState>

Starts observing foreground events and automatically checks the WebView health.

Returns: Promise<GuardianState>

stopMonitoring()

stopMonitoring() => Promise<GuardianState>

Stops any automatic foreground monitoring.

Returns: Promise<GuardianState>

getState()

getState() => Promise<GuardianState>

Returns the latest known monitoring state.

Returns: Promise<GuardianState>

checkNow(...)

checkNow(options?: CheckNowOptions | undefined) => Promise<CheckResult>

Forces a WebView health probe immediately.

Returns: Promise<CheckResult>

addListener('foreground' | 'webviewHealthy' | 'webviewCrashed' | 'webviewRestarted', ...)

addListener(eventName: 'foreground' | 'webviewHealthy' | 'webviewCrashed' | 'webviewRestarted', listenerFunc: (event: GuardianEvent) => void) => Promise<PluginListenerHandle>

Returns: Promise<PluginListenerHandle>

Interfaces

GuardianState

StartMonitoringOptions

CheckResult

CheckNowOptions

PluginListenerHandle

Type Aliases

RestartStrategy

'reload' | 'reloadFromOrigin' | 'customUrl'

GuardianEvent

GuardianState