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You can add custom plugins to tinymce 4 using the "External plugins to load" entry. Name should be the name of the plugin and URL is the URL TinyMCE 4 will try to load dynamically using AJAX.
Add the following path to your client folder: "external/wysiwyg/tinymce4/contenido/client_plugins/plugins".
Put the plugins (which are folders) to load inside the latter folder. Contenido tries to load the following files in each plugin "plugin.min.js" and then "plugin.js". If either of these files is found they are loaded into Tinymce.
Add config variable "tinymce4" -> "contenido_load_client_plugins" with content "true".
Add config variable "tinymce4" -> "contenido_load_all_client_plugins" with content "true".
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To load several plugins enter one plugin and save the form using the save button. One can then add another plugin. If more than 2 external plugins are wished then save the form and enter another one (the same applies for adding even more plugins).
Add the following path to your client folder: "external/wysiwyg/tinymce4/contenido/client_plugins/plugins".
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