Handle storage loss

Safari’s Intelligent Tracking Prevention (ITP) can clear localStorage after periods of inactivity. Because Portal stores the user’s signing share in localStorage, the share may be missing the next time a user opens your app. The SDK invokes any onWalletNotOnDevice listeners during initialization when it detects this has happened.

Detecting storage loss

Register your listener as early as possible. If the event already fired before you subscribed, the callback is replayed automatically.

portal.onWalletNotOnDevice(async (payload) => {
  if (payload.isBackedUp) {
    // Guide the user through wallet recovery
  } else {
    // No backup exists — clear state and restart onboarding
    await portal.clearLocalWallet()
  }
})

The callback receives a WalletNotOnDevicePayload:

Field	Type	Description
`clientId`	`string`	The client ID of the affected wallet
`isBackedUp`	`boolean`	Whether a backup exists that can be used to recover
`reason`	`'storage_cleared'`	Why the wallet is not on device

isBackedUp: true — direct the user to recover their wallet.
isBackedUp: false — call clearLocalWallet() and restart the wallet creation flow.

Next steps

Recover a wallet — step-by-step recovery flow to direct users to when isBackedUp is true.
Create a wallet — restart onboarding when no backup exists.

Manage wallet lifecycle states Web authentication methods

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Handle storage loss

Detecting storage loss

Next steps

​Detecting storage loss

​Next steps

Detecting storage loss

Next steps