Many thanks to A1ex, Licaon_Kter, dfort, and dpjpandone for your efforts to improve ML for the EOS M, and making possible this new nightly build !
I do not shoot video, but I'm glad to see that an old issue with A-ETTR present in previous builds for EOS-M seems fixed now.
ETTR worked in previous versions, but the "ETTR ..." on-screen message during exposure adjust locked and did not dissapear until I pressed the shutter button. So I needed to look at ETTR hint in RAW histobar to know if A-ETTR had already fiinished calculation or not. With the new build, this issue is gone, A-ETTR works fine.
Thanks again !