Assets\Coffee\UIExtensions\SoftMaskForUGUI\Scripts\SoftMask.cs(417,33): error CS1061: 'Camera' does not contain a definition for 'reviousViewProjectionMatrix' and no accessible extension method 'reviousViewProjectionMatrix' accepting a first argument of type 'Camera' could be found (are you missing a using directive or an assembly reference?)
Assets\Coffee\UIExtensions\SoftMaskForUGUI\Scripts\SoftMask.cs(417,33): error CS1061: 'Camera' does not contain a definition for 'reviousViewProjectionMatrix' and no accessible extension method 'reviousViewProjectionMatrix' accepting a first argument of type 'Camera' could be found (are you missing a using directive or an assembly reference?)
https://github.com/mob-sakai/SoftMaskForUGUI/blob/bffaed3d78257edcb0f50562eae3fb6933e98010/Assets/Coffee/UIExtensions/SoftMaskForUGUI/Scripts/SoftMask.cs#L417 modify to:
Matrix4x4 previousVP = cam.previousViewProjectionMatrix;