I am looking for a widget that I can plug in to my ASP.NET site that will allow users to create math formulas with their associated MathML. Ideally this would be similar to an HTML editor like TinyMCE.
There have been solutions in the past (see MathML, Latex or similar for web-based WYSIWYG editor), but everything I find seems to have been discontinued.
Free and open source is preferred but we do have a budget or 3rd party tools.
There are tools which use a derivative of ASCIIMathML.js, but most encapsulate the editor widget inside a larger framework or content management system: