With these two buttons missing in order to streamline the Stage, here a simple request to bring this feature back. Hold down any two effect buttons (say A and C) at the same time, All four (ABCD) are selected to edit/save as a group the way the Head did when you held the Stomps button. And similarly with holding down any two of the effects section, bring the whole effects section into focus. This performs the identical function as those buttons did on the head with perfect ease, yet without needing dedicated buttons for this feature. My guess is that for whatever reason, they don't want to include this feature in the future, as they curiously left it out of the Editor as well.
Locking the whole section takes a few seconds, so that will be my workaround when not using the editor. Still, I did find it useful to create sectional presets which are easier to recall than browsing rigs, locking the four blocks, returning to the new rig, saving, unlocking the four blocks
*If it would be a greater programing hassle to add all the combinations of "any two" just make it work when you press and hold A&B and X&Mod