fix(webui): don't fail when backend or frontend are empty.
fix(webui): don't fail when backend or frontend are empty.

nmengin/traefik,martinbaillie/traefik,containous/traefik,martinbaillie/traefik,containous/traefik,EmileVauge/traefik,thomasbach76/traefik,dtomcej/traefik,timoreimann/traefik,FriggaHel/traefik,EmileVauge/traefik,vdemeester/traefik,marco-jantke/traefik,ldez/traefik,tanyadegurechaff/traefik,tanyadegurechaff/traefik,dtomcej/traefik,mildis/traefik,thomasbach76/traefik,mvdstam/traefik,ldez/traefik,vdemeester/traefik,aantono/traefik,tanyadegurechaff/traefik,marco-jantke/traefik,adityacs/traefik,mihaitodor/traefik,nmengin/traefik,SantoDE/traefik,SantoDE/traefik,adityacs/traefik,adityacs/traefik,mildis/traefik,mihaitodor/traefik,vdemeester/traefik,mihaitodor/traefik,mmatur/traefik,dtomcej/traefik,ldez/traefik,mmatur/traefik,martinbaillie/traefik,mildis/traefik,bparli/traefik,aantono/traefik,mildis/traefik,mvdstam/traefik,thomasbach76/traefik,bparli/traefik,martinbaillie/traefik,marco-jantke/traefik,EmileVauge/traefik,mmatur/traefik,adityacs/traefik,bparli/traefik,timoreimann/traefik,mvdstam/traefik,containous/traefik,aantono/traefik,EmileVauge/traefik,aantono/traefik,timoreimann/traefik,mvdstam/traefik,timoreimann/traefik,mihaitodor/traefik,dtomcej/traefik,SantoDE/traefik,nmengin/traefik,SantoDE/traefik,tanyadegurechaff/traefik,vdemeester/traefik,ldez/traefik,aantono/traefik,mmatur/traefik,nmengin/traefik,containous/traefik,FriggaHel/traefik,FriggaHel/traefik,FriggaHel/traefik,marco-jantke/traefik,thomasbach76/traefik,bparli/traefik