Changing mobile toolbar icons

[d-con]

Hi, I’m trying to change icons for command buttons on the mobile toolbar, and there are several indications that I should be able to do so, but I’m not finding any way to actually do it. On the Commander Mobile Toolbar settings, there’s a random Header that says “Custom Icons” but no fields underneath that I can see that relates to it. When I try to click on the icon itself in the Obsidian Mobile Toolbar menu, there’s a highlight state, but no window for changing pops up like it does for the Ribbon menu.

Am I mistaken that I should be able to do this? I’m using Obsidian on an iPad.