A block-sender button (add to twitlist).

webv4/components/twit-button.xjs

+<? var _bs = locale.get('button_block_sender', 'page_forum'); ?>
+<button id="bsb-%s" class="btn btn-default icon" aria-label="<? write(_bs); ?>" title="<? write(_bs); ?>" onclick="blockSender('%s', '%s', '%s')">
+    <span class="glyphicon glyphicon-ban-circle"></span>
+</button>
\ No newline at end of file