Or you could just use the following in your extra.less
span.u-concealed {
display: none;
}
.p-footer-copyright { display: none; }
It works for me on XF 2.1.12 and also worked on XF 2.2.3 and 2.2.4
(If i recall correct, just the bottom line works)
.p-footer-copyright { display: none; }
Just put in your extra.less for each style U use and save or save and exit