Cannot Edit / See OM Systems OM-5 raw files (.orf format) in Apple Photos

When I imports photos from my OM Systems (previously Olympus) OM-5 Camera into photos, the jpegs import and I can edit them. The corresponding raw files import, but simply appear as grey boxes, and I cannot edit them. When I try to switch the original file from jpeg to raw, Photos is unable to open the OM-5 raw formatted files. Is there an update / download / plug-in I need that so that Photos can read the OM-5 raw (.orf) formatted images? I have an older Pen E-PL10 camera, also by Olympus (now OM Systems), and Photos can open and I can view / edit those raw files.