Feature Request: toggle to glayscale Primay/Secondary Color when enter/exit mask paint mode

[Yulit-c]

When entering the layer mask editing mode, it stores the RGB Primary Color & Secondary Color information while switching to grayscale Primary Color & Secondary Color, and restores the RGB Primary Color & Secondary Color of RGB is restored when the mask is finished editing.

This allows workflows that use layer masks to run faster.

If possible, it may be even more useful to store the Primary Color & Secondary Color in Layer Mask Edit mode as well!

[Yulit-c]

The expected behavior is shown in the following image.