Given the issues with XQuartz under Tahoe it is not surprising that MOE from Chemical Computing Group does not run.
We have learned that MOE will not launch on macOS 26 (Tahoe), released on September 16, 2025.
To continue accessing MOE, please refrain from upgrading beyond macOS 15 Sequoia (last supported version: 15.7) while we work to address Apple’s latest release.
If you have technical questions, please contact support at support@chemcomp.com