in js/details.js [557:572]
function updateButtonsState() {
let list = getCheckedBugIds();
let enabled = list.length > 0;
let single = list.length == 1;
if (NeedInfoConfig.api_key.length == 0) {
enabled = false;
}
// blanket update all buttons
updateButtonState(enabled);
// spam blocking prevents this
if (enabled) {
document.getElementById('button-clearcmt').disabled = !single;
}
}