How can I wire up a paste_preprocess callback in TinyMCE Blazor?

I'm using TinyMCE in a Blazor WASM app using the TinyMCE Blazor integration, but would like to wire up the paste_preprocess callback so I can pre-process the content copied from the clipboard, before it hits the TinyMCE editor.

I'd like to do the pre-processing in the C# code, rather than having to write Javascript to do it. How do I wire up a callback to do this? My TinyMCE configuration is initialised in C# code.