when trying to customize add-ons down on the status bar, several on the far-right are 'locked in place'.
Does this 'grayed-out area' have anything to do with- 'all of the add-ons that you installed before you loaded the Theme Font & Size Changer' ?
Alle antwurden (1)
Not all buttons that are added by extensions can be moved to another toolbar.
So it is possible that those buttons are added by an extension that only supports the Add-on bar for their buttons.