Mac Metal issues
Capture 2020 requires more from Apple's 3D graphics API Metal than any previous Capture version. Unfortunately several Metal GPU drivers suffer from issues and stability problems.
(1) - Driver crash issues affect specific projects. Apple Feedback issue FB6101284 filed May 27th 2019.
(2) - Driver issues cause unreliable automatic rendering quality on macOS versions prior to 11.1. Apple Feedback issue FB7625102 filed March 13th 2020. Use fixed rendering quality as a workaround.