iMovie doesn't show photos from my photo library
When I import a photo from my photo library to my iMovie project, and I drag it into my time line, it the photo turns black. I tried with downloaded photos from random places and they work fine in iMovie. I also tried sending photos from my photo library to my mail and then downloading, but still I have the same problem... Please help!
MacBook Pro, macOS High Sierra (10.13.4)