every now and then I have a disappearing pin in camera raw with the radial filter. Hence, no adjustments possible anymore as I cannot select the filter anymore. Initial adjustments are still visble, but the radial just disappeared. Needless to say that this is extremely annoying.
Never seen this. But it might help, can't really hurt to try resetting your preferences for ACR:Hold down the Command key and select Photoshop > Preferences > Camera Raw (macOS) or hold down the Ctrl key and select Edit > Preferences > Camera Raw (Windows). Click Yes in the dialog that asks "Delete the Camera Raw Preferences?" See also: https://helpx.adobe.com/camera-raw/using/camera-raw-settings.html
Author “Color Management for Photographers" & "Photoshop CC Color Management/pluralsight"