[Bug Report] the tonemapper dose not enabled following the documentation page not on 4.17 or 4.18 i guess since "r.mobile.tonmapperfilm" command was added! it a bug?

hey i think there is a bug in the newer versions of ue like “4.17/4.18” with the tonemapper as i can’t enable it on my mobile devices by any means i followed the documentation by letter on 4.18 and 4.17 but still cant enable it i thing
that was when the command “r.mobile.tonmapperfilm” was added to the engine and thats somehow stoped “r.tonemapper film” to work on mobile and i cant enable the tonemapper from the ini file using “r.mobile.tonmapperfilm”
is it a bug or i miss something please help???.
forgive my english.