Hi,
I've also noticed that since 2.5.0 there's a slight problem with the display of button states in this section, and the same is true for menu item edition and the three buttons there for "Show image", "Show description" and "Published", too. All other buttons work fine.
However, I figured it's only the display of the button state. If you click on the alternate (grey) button, the buttons don't change their state very clearly but only very slightly - see here:
Before:
After:
Notice the slight change in the bevelling and color of both grey and red buttons.
As you say, the function works fine, actually. So, I didn't dig deeper, but got used to it: as you say, just click the grey button, then "Save", and the page will return with desired and correct button states.
Latest now since it's mentioned here, I bet HikaShop peeps are going to fix it for the next version. Meanwhile, the important thing is that you didn't lose functionality.