After Effects Software Bug - Version 18.1.0 (Build 38)
In this build, there's a bug that causes this error: "After Effects error: could not parse mask shape on clipboard." This occurs when ever there is any content from Illustrator in the clipboard. The error repeats consistently until the clipboard is replaced with non-Illustrator content. Please fix.
Richard Hayes commented
This error/bug still exists in the latest version of After Effects 2021.