When a user inadvertently enters HTML into a 'Short text' custom field, the HTML will be stripped and saved with no error notification for the user (same here for the title in a course name field). For example:

Entered:

Score <60% some more text

Saved result:

Score

Before saving, the data should be validated for HTML existence and if found, display a suitable error message to the user.

We would need to show a validation error message instead of just removing the unwanted text.