IMPORTANT: You must disable the Network Service Sandboxing in the registry setting to make sure that DLP doesn't stop working.
NOTE: For details about how to determine the settings, see
Network Service Sandbox Early Access.
To disable the Network Service Sandboxing, apply the following via GPO:
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge -> key: NetworkServiceSandboxEnabled, value: [DWORD 0]
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome\ -> key: NetworkServiceSandboxEnabled, value: [DWORD 0]
Or via the enterprise policy
NetworkServiceSandboxEnabled (see the link above).