prevent converting special characters to html entities ngx-editor

Question

i am using some mathml tags inside the ngx-editor like this

<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>2</mn><mn>5</mn></mfrac></math>

as you see there are some special characters inside mathml codes that i dont want to convert to html entites because this mathml code will render by mathjax later how can i insert this as plain text? or is there any solution for this?

this is rendered encoded text

<p>   &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mfrac&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;/mfrac&gt;&lt;/math&gt;</p>

any help will highly appreciated