function addLoadEvent(func) { var oldonload = window.onload; if (typeof window.onload != 'function') { window.onload = func; } else { window.onload = function() { if (oldonload) { oldonload(); } func(); } } } function tabber(){ let navTabs = document.getElementsByClassName("nav-tabs"); let selectAll = function(ind){ for(let navTab of navTabs){ let dom = navTab.childNodes[ind]; let old = dom.onclick; dom.onclick = null; dom.click(); dom.onclick = old; } } let registerAll = function(){ for(let navTab of navTabs){ let commandLineTab = navTab.childNodes[0]; let pythonTab = navTab.childNodes[1]; commandLineTab.onclick = function(){ selectAll(0); } pythonTab.onclick = function(){ selectAll(1); } } } registerAll(); }; addLoadEvent(tabber);