On the laptop, open http://127.0.0.1:8766/ (the approval page works only on the laptop itself). Approve this phone only if it shows these same symbols:
The symbols identify this phone's own access key, so you approve the right phone. They do not check the HTTPS connection; the browser checks that separately.
One approval on the laptop allows this phone on both the laptop and the server.
Optional: in the browser menu, choose "Add to Home screen" to open this page like an app. The browser can still clear its saved data.