「特定色域の選択」のインターフェイス

@L K J Unfortunately, it is almost never possible to revert to a previous interface design within the same version of a software. When a major UI change like this is implemented in an update, it's typically a permanent part of that version and all subsequent updates. The developers remove the old code and replace it with the new, making it impossible to simply "switch back."  Unless you roll back to the previous verson, negating the 'update' — You would have to uninstall your current version and then install the older one! 

Your best bet is to spend some time exploring the new interface to understand its functionality. The new sliders and controls have the same core functionality as the old ones, just with a different visual presentation. The best approach is to spend some time getting familiar with how the new sliders and gradients work.