Alt + right click dragging does not change brush size in liquify (wacom)

Hello,
Normally, ALT+RMB+Drag is the way I change brush size on the canvas. On previous versions this also worked in Liquify but now it doesn't when using a wacom pen with one of the buttons configured as right click. When using the mouse, it does work like it should.

I wonder why there's no consistency between the Photoshop application and the Liquify tool in this area. The keyboard shortcuts to change brush size as defined in the keyboard shortcuts never worked in liquify and now this. Is this a bug or a feature?