Following the latest macOS Monterey 12.3 update, users are reporting several problems when using external monitors, ranging from Macs not detecting displays at all to inaccurate screen output, according to posts on the Apple Support and MacRumors forums.
In the ten days since the update became available to the public, users have already reported issues with the update bricking Macs that have had logic board replacements and problems with using game controllers. Adding to the list of issues, users are now reporting that the update is causing problems with external monitors.
According to users on the Apple Support and MacRumors forums, some external displays connected over USB-C are no longer detected by Macs after updating to the latest macOS update.
Read more at MacRumors.com