I’ve had this happen several times already on different days, both before and after the latest update.
Once Zwift loads, it will not detect mouse clicks on the buttons. Sometimes I need to click 4 - 5 times before the button registers the click. This happens on the device pairing screen at start, ride type/route selection screen at start, and at the save ride screen at the end.
This only happens in Zwift. All my other apps, included macOS respond correctly at the time this is happening.