WordPress fix Reply To: tinymce not working until add define(‘SCRIPT_DEBUG’, true)

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Reply To: tinymce not working until add define(‘SCRIPT_DEBUG’, true), by Rhand

Well either I am thinking a JavaScript conflict because of plugins or a theme which you could test by deactivating plugins, using another theme and checking all while adding a plugin used one by one.
If that is not it another issue could be corrupted or hacked WordPress files. See https://wordpress.org/support/topic/editor-is-blank-cant-edit-postspages-with-editor/ where they discuss a similar issue. They and I recommend to overwrite all core files – wp-admin folder should suffice – with a new copy and see if that solves the issue. See https://codex.wordpress.org/Updating_WordPress#Manual_Update for details

Reply To: tinymce not working until add define(‘SCRIPT_DEBUG’, true)