You can only use this feature on your main device (typically your smartphone).
The Open links in your default browser setting lets you open links in chats with the browser you've configured on your device (e.g. Safari, Chrome).
To open links in your default browser:
1. Open LINE on the main device your account is registered to.
2. Tap the Home tab >
> LINE Labs.
> LINE Labs.3. Turn ON Open links in your default browser.