Just noticed after an upgrade from UCCX 10.6 to 11.6 that IE11-settings can become troublesome.
Login and call-handling actually worked as expected, but it was impossible to load CUIC-based gadgets.
- Document mode must be set to Edge.
- Compatibility mode must be set to Off.
- If Enterprise Mode is running, the URL(s) should be set to apply Desktop profile.
- Also, if running Chrome instead, remember that recent versions require the CN to be included as a SAN as well in the certificate to avoid warnings.