How to delete QQ space talk in batches?

When I was young and ignorant, I said a bunch of messy things in QQ space. Now want to delete.
js code is:

var delay = 1000;
function del() { document.querySelector('.app_canvas_frame').contentDocument.querySelector('.del_btn').click(); setTimeout("yes()", delay); } 
function yes() { document.querySelector('.qz_dialog_layer_btn').click(); setTimeout("del()", delay); } 
del();