copy labels.js

var match = location.href.match(/trello\.com\/([[cb])\/(.*)\//),
    boardId;
    
if (match[1] === 'c') {
  boardId = window.IdCache.getBoardIdForCard(match[2]);
} else {
  boardId = window.IdCache.getBoardId(match[2]);
}

$.ajax('/1/boards/' + boardId).then(function(board) {
  localStorage.setItem('copiedLabels', JSON.stringify(board.labelNames));
  console.log('Copied labels:', board.labelNames);
});