(adsbygoogle = window.adsbygoogle || []).push({});
All you have to do is put this in the URL Browser
javascript:document.getElementById("channel-base-div").
id="comment_entry_submit_button"
;add_comment('user_comments', 'TYPE COMMENT HERE', false, 10);
Then where is says "Type Comment Here" put the comment you want then click enter, then look you posted a comment!!!
hope this helped you out!