I think it would be very useful to have the option to manually expand the width of the Elements Tree/Elements side-panel (I think this may have been suggested before, but I couldn’t find a thread on it).
Even with giving elements short, abbreviated labels, it can be hard to see certain elements’ names within the elements tree, when they are within multiple nested groups.
Having the option to expand the width of the panel (even if it were to temporarily cause the panel to overlap with the page in the editor) would make it much easier to read and see the full elements’ names in the tree. 