Extract your Widevine L3 CDM from your Android device (Doesn't work with: Xiaomi, Samsung, General Android Emulators, and Huawei devices. Works with everything else + Android VMs): https://github.com/wvdumper/dumper
Proper Instructions:

Requirements and programs

- Rooted phone, if you don't have root you can make a temporary one with "Mtk easy su" + "Magisk manager"
- Install FridaServer from the play store, install server with the FridaServer application "download server" option (in my case it was 15.1.9)
- Python 3.9.6 (Python 3.10 does not work)
- ADB, you can download it from here https://dl.google.com/android/repository/platform-tools-latest-windows.zip