Many modules insert lines like these into your build.prop:

ro.telephony.default_network=9
persist.radio.lte.enable=true
persist.radio.calls.on.ims=1

These commands tell the Android system to prefer LTE networks and enable Voice over LTE (VoLTE). The number 9 typically represents "LTE/CDMA/EvDo/GSM/WCDMA" – essentially a global mode forcing 4G priority.

#MAGISK

Most modern Magisk versions ignore the script content, but the files must exist.

Carriers often "hand down" your connection to 3G during low activity to save bandwidth. A 4G Magisk module can force your phone to stay on LTE exclusively, eliminating the handover delay when you start browsing again.