With MR !3670 the default networking gadget on postmarketOS has changed from RNDIS (Remote Network Driver Interface Specification) to NCM (Network Control Model). There should be no noticeable change for most users.
The only known incompatibility is the absence of a NCM driver on Windows 10 and lower. See the Windows FAQ on the postmarketOS wiki for more details. Windows 11 is not affected and should continue to work as expected.
In case you want to continue using RNDIS for whatever reason, you can add the following line to your /etc/deviceinfo file and run sudo mkinitfs:
deviceinfo_usb_network_function="rndis.usb0"
In case you experience any issues, please open an issue in the pmaports issue tracker and let us know.