Does not work on Microsoft Edge either. All browsers have the same issues, including having text and panes overlapping in a separate ("advanced") reply screen. There also all browsers display these error messages on the top of the page:
Warning: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in
..../includes/class_wysiwygparser.php on line
310
Warning: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in
..../includes/class_wysiwygparser.php on line
310
Warning: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in
..../includes/class_wysiwygparser.php on line
402
Warning: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in
..../includes/class_wysiwygparser.php on line
462
Warning: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in
..../includes/class_wysiwygparser.php on line
462