For users on macOS High Sierra, was a mandatory update to ensure media compatibility with newer iPhones. However, for those with older hardware or a preference for the iMovie 9 workflow, it felt like a downgrade in efficiency.
Released in April 2018, served as a targeted maintenance update for macOS High Sierra (10.13.2+) users. While it successfully introduced essential support for modern mobile formats like the iPhone X , its reception was polarized due to performance regressions and a continued departure from the beloved workflow of iMovie 9. Key Features & Enhancements
If you are looking for a modern alternative in 2026, Filmage Editor is often recommended as a familiar but more flexible step up. If you’d like more help, let me know: The you are currently running iMovie 10.1.9
: Users reported significant slowdowns in import times—sometimes jumping from minutes to over an hour—and frequent "Can't Encode" errors during export.
Addressed a bug where opacity controls would vanish for users in German or Polish languages. For users on macOS High Sierra, was a
: Resolved critical issues where HEVC video clips and HEIF photos would incorrectly appear black in the viewer. Bug Fixes :
: Long-time users lamented the loss of specific tools such as chapter markers , sharing directly to iDVD, and certain QuickTime export options. Verdict: A Necessary Patch for High Sierra Addressed a bug where opacity controls would vanish
If you're having a (like black screens or export fails)