platform_manifest_twrp_omni/twrp-extras.xml

<?xml version="1.0" encoding="UTF-8"?>
<manifest>
    <remote name="TeamWin"
            fetch="https://github.com/TeamWin"
            review="https://gerrit.twrp.me" />

<!-- TWRP lives in TeamWin android-9.0 (not AOSP!) -->
    <remove-project name="platform/bootable/recovery"/>
    <project path="bootable/recovery" name="android_bootable_recovery" remote="TeamWin" revision="android-9.0"/>

<!-- Use TeamWin fork for repacker support -->
  <remove-project name="android_build" />
  <project path="build/make" name="android_build" remote="TeamWin" revision="android-9.0" groups="pdk" >
    <copyfile src="core/root.mk" dest="Makefile" />
    <linkfile src="CleanSpec.mk" dest="build/CleanSpec.mk" />
    <linkfile src="buildspec.mk.default" dest="build/buildspec.mk.default" />
    <linkfile src="core" dest="build/core" />
    <linkfile src="envsetup.sh" dest="build/envsetup.sh" />
    <linkfile src="target" dest="build/target" />
    <linkfile src="tools" dest="build/tools" />
  </project>

<!-- Include external Magisk repo for repack binaries -->
    <project path="external/magisk-prebuilt" name="external_magisk-prebuilt" remote="TeamWin" revision="android-9.0" />

    <project path="external/python3" name="android_external_python3" remote="TeamWin" revision="android-9.0"/>

<!-- Include TeamWin android_system_update_engine to build a good update_engine_sideload -->
    <project path="system/update_engine" name="android_system_update_engine" remote="TeamWin" revision="android-9.0" />
</manifest>