Paper_lantern theme icons/layout may not fit everyone, fortunatelly cPanel was so kind to provide X3 based style for the paper_lantern theme.

X3 style will make paper_lanter icons and layout look like old classic X3.

Here is how to change all paper_lantern cPanels to use X3 style (i mean it will not change paper_lanter to x3 for them, it will leave paper_lantern and just use X3 styling)

mkdir /var/cpanel/customizations/styled

ln -s /usr/local/cpanel/base/frontend/paper_lantern/styled/retro /var/cpanel/customizations/styled/default_style

If one need to change theme (not style) for cpanels, one can use WHM / Multi Account Functions