Hi joerndaberkow,
I got this same error in 1.8.2. I got rid of the error message by editing the file “wp-content/plugins/diamond-multisite-widgets/diamond-recent-comments.php” and adding and empty string as an additional argument in the call.
The original row 61
$output .= $this->render_output($wgt_miss, $wgt_count, $wgt_format, $wgt_avsize, $wgt_defav, $wgt_dt, '<li>', '</li>', '<ul>', '</ul>', $wgt_white);
was changed to
$output .= $this->render_output($wgt_miss, $wgt_count, $wgt_format, $wgt_avsize, $wgt_defav, $wgt_dt, '<li>', '</li>', '<ul>', '</ul>', $wgt_white, '');
I have no idea though if this has any other effects, or what the argument are for. This fix might of course be reverted at the next plugin update (but perhaps with the real fix). 🙂
Hope it helps,
/John
