How to leave inner text unchanged?

I am trying to update from 0.48.x to 0.55.0. The reason I try to update Hugo version is because one time I did not update for 1 yr and then the site will not compile when we wanted some the new features of Hugo.

The more general question is should the inner text of a <textarea> in a markdown file be compiled into HTML or should it be left as-is. What is the right behavior of Hugo and was this changed intentionally? If yes, was there any test case or reason for this?