I am the author of the Black Studio TinyMCE plugin. An user reported a compatibility issue between my plugin and yours. Please see the original post for further info (I also wrote a temporary patch there).
It seems the problem is generated by code on WP Page Widgets which calls some Black Studio TinyMCE functions, but it causes problems in some admin pages.
I found 2 different issues:
1. The function
pw_admin_head should be hooked to
admin_init and not to
edit-tags.php page, it is necessary to check for the presence
action=edit parameter in the url, to distinguish the taxonomy editing mode from the listing mode (in the latter the
action parameter is not set).
By the way, I believe it would be better to perform those operations on the Black Studio TinyMCE side, because the initialization code of the plugin may change in the future, and it's easier to maintain it on my side. In the last months I already added some compatibility code for WP Page Widgets on my plugin, but it was only for posts & pages. I may extend it, and include also taxonomies and search/front page. In that case you should remove your
Please let me know if you have any comments about this issue.