macOS Catalina Security Update 2021-007 iScreensaver and WebGL

It appears that the recent update to macOS 10.15.7 Catalina (Security Update 2021-007, released on 25 October 2021) causes WebGL to fail on certain Macintosh models. This affects all websites that use WebGL. as well as applications that use WebKit.

See for example:
It appears that Mid-2012 Macbook Pros running Catalina have …https://www.reddit.com1. ‚Ä∫ apple ‚Ä∫ comments ‚Ä∫ it_appear…
2021-007 Security Update Catalina causes - Apple Support …https://discussions.apple.com1. ‚Ä∫ … ‚Ä∫ MacBook Pro

Since iScreensaver uses WebKit and WebGL internally, this also affects iScreensaver.

We are following the issues and will report back here if there is an update to fix the problem.

Update: we are seeing this issue on a 2012 MacBook Pro. The problem exists with Safari 14.1 as well as Safari 15.1.

The last time a software update broke functions like this ( see https://iscreensaver.com/forum/discussion/541/solved-security-update-2020-005-breaks-swift-based-screensavers#latest ) Apple released another update to fix the problem, and they had the fix ready in about one week.

We hope and expect something similar will happen soon, and will update this thread once we know more.