after-the-deadline.php) and I saw that there's a function
AtD_should_load_on_page which is checked by the functions that adds js/css, but it's not checkd by functions that modify the TinyMCE configuration (namely
AtD_change_mce_settings), so in widgets.php admin page this causes an error when an editor is loaded. I think that either "After the Deadline" should load fully on every admin page or load only in selected pages but without interfering with editor that may be present in other admin pages. It also would be nice to have a way (hooks/functions/...) to access to "After the Deadline" by other plugins (i.e. force it to be on or off on a specific page, ...).
At the moment I fixed the issue on my plugin with a workaround (by explicitely detecting the presence of "After the Deadline" and removing their filters before loading the editor), but I would prefer a more robust solution.
Thanks for your attention.