javascript - How to validate input from Chrome's Inspect tool?

Question

Seterra is a site that provides geography quizzes. Once you finish a quiz, it has a pop-up window that gives you the percent you got correct and the time it took you to complete it (i.e. "96% 3:07"). Users can screenshot this pop-up as evidence of their score.

If I inspect the element in Chrome, it has a clever alt attribute warning users not to cheat. If I willfully ignore it, I can change my time score, or decrease my percentage score with no issue. However, if I try to increase my percentage, the pop-up component will flash a red color and revert to my original percentage.

So essentially, the frontend appears to be validating input from the Inspect tool and responsively rendering the pop-up. Could someone provide resources on how a developer/engineer might configure this?

<div 
  alt="Remember: honesty is the first chapter of the  book of wisdom." 
>
  96%    3:07
</div>

Answer 1

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