How can I prevent the Web Push subscription widget from closing when a user clicks outside of it?

The built-in subscription prompt widget hides itself as soon as the user clicks anywhere outside it. That behaviour is hardcoded in the widget — there is no initialization option to disable it.

To get a dialog that stays open until the user makes a choice, do not enable the built-in widget: render your own UI and trigger the subscription yourself.

How to implement

1. Initialize the SDK without the prompt/popup widgets — simply leave subscribePopup and subscribeWidget out of your init parameters (or set enable: false), and do not import/run PWSubscribePopupWidget or PWSubscriptionPromptWidget.
2. Build your own modal with your own HTML/CSS/JS, so you fully control when it closes.
3. When the user clicks your “Allow” button, call the SDK’s subscribe() method — this shows the native browser permission prompt and registers the subscriber.

const pushwoosh = new Pushwoosh();

pushwoosh.push(['init', {
    applicationCode: 'XXXXX-XXXXX',
    serviceWorkerUrl: '/service-worker.js'
    // no subscribePopup / subscribeWidget -> no auto-closing widget
}]);

// call from your own "Allow" button handler:
myAllowButton.addEventListener('click', () => {
    pushwoosh.subscribe();
});

Note: Pushwoosh.push(['subscribe']) is not a valid command and will throw Unknown command! — use the subscribe() method on the Pushwoosh instance. Init parameters for the standard widgets are subscribePopup and subscribeWidget; there is no customPopup parameter.

See the documentation on Custom subscription popup for the available styling options.