>>81818
Something like this could work. Use some scripting addon.

var selectAllButt = document.createElement("INPUT");
var reportsForm = document.getElementById("reportDiv");
selectAllButt.type = "button";
selectAllButt.value = "Select all reports";
reportsForm.parentElement.appendChild(selectAllButt);
selectAllButt.onclick = function() {
  chckAllBoxes();
}

var reportsCboxes = document.querySelectorAll("#reportDiv [type=checkbox]");

function chckAllBoxes() {
  for (var i = 0;  i < reportsCboxes.length; i++) {
    reportsCboxes[i].checked = "true";
  }
}