On a 2017 iMac in Lightroom, the new Color Efex Pro 5 apparently now offers support for PSD files but when I try to open such a file from LR, Color Efex opens normally but immediately displays an error message saying it does not support such files (screen shot attached). LR external editing setting is set to PSD for Color Efex. Are PSD files now supported from LR or not?
Nik tools support JPEG and TIFF format only → https://support.dxo.com/hc/en-us/articles/5091196651037-Which-file-formats-are-supported-for-use-with-Nik-Collection-