Gets disconnected / "kicked" out of Wi-Fi in standby (screen off)

This used to have somewhat of a fix on 16.04 but it wasn't brought over to 20.04 due to causing issues on other devices (see ubports/development/core/packaging/network-manager#1 (closed) for example).

Sometimes the netwoprk indicator just shows the "0% signal" icon when pressing power button to wake up the device, other times it prompts for the network password immediately.

To reconnect back to the network the Wi-Fi toggle can be used, and then tapping on the network should reconnect.