So here are the things you need to know about Magento 2.3. Tinymce is not supported from Magento 2.3 onwards.
You might have extensions that used to work in Magento 2.2 and Magento 2.1 but in Magento 2.3 now wysiwyg editor wont load stating tinymce error. So what can be done ??
Easy just find the js file which define([“tinymce”]) instead of that just replace tinymce with define([“wysiwygAdapter”]) and change all the occurance of tinymce to wysiwygAdapter and there you go your error is removed and its working again. If still you cant solve it contact us. We will be happy to help you out.
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