Customise TinyMCE editor in Episerver 9 - tinymce

Question

I am working on Episerver 9. I have a requirement where user can copy content (which includes HTML tags) into the TinyMCE editor.
I want only the text content to be pasted. HTML tags should be filtered out automatically by default.
Is there any way to achieve this using TinyMCE?

Answer 1

You can register a custom TinyMCE plugin in Episerver using the TinyMCEPluginNonVisual attribute. By setting AlwaysEnabled to false, you can use property settings to determine whether the plugin should be enabled or not for a specific editor/XHTML property.
[TinyMCEPluginNonVisual(AlwaysEnabled = false, PlugInName = "customplugin")]
public class MyCustomPlugin
{
}
Your actual TinyMCE plugin (i.e. JavaScript code) could be something like the following:
(function (tinymce, $) {
tinymce.create('tinymce.plugins.customplugin', {
init: function (editor, url) {
editor.onPaste.add(function (editor, event) {
if (!event.clipboardData || !event.clipboardData.items) {
return;
}
// TODO Modify event.clipboardData, for example to strip out HTML tags
});
}
});
// Register plugin
tinymce.PluginManager.add('customplugin', tinymce.plugins.customplugin);
}(tinymce, epiJQuery));
While this isn't a complete example, it should get you started in the right direction.
You should also have a look at the official documentation.
Edit: If you just want to alter the paste_as_text setting, you could register a plugin and set the configuration through the TinyMCEPluginNonVisual attribute:
[TinyMCEPluginNonVisual(EditorInitConfigurationOptions = "{ paste_as_text: true }")]
public class PasteAsTextPlugin
{
}

Answer 2

Assuming that you are loading the paste plugin you can force TinyMCE to always paste as plain text with the following:
tinymce.init({
...
plugins: "paste",
paste_as_text: true
...
});
https://www.tinymce.com/docs/plugins/paste/#paste_as_text
I would assume that Episerver provides you some way to manipulate the configuration of TinyMCE. Adding the paste_as_text option to that configuration should do what you need.