Why 404 error showing if I go to inspection tool?

Question

I found that on this page https://www.ofwteleserye.su/its-showtime-may-2-2022/ if I try to go to the inspection tool the video of this page instantly shows "404 No Video Found". What is the reason behind that? How to solve this issue? I have tried different browsers but found the same issue. I don't have detailed knowledge of HTML. Image attached.

It's the problem at your end since it works perfectly fine for me when I open it. — Archit Gargi, May 02 '22 at 11:52
there's probably an event firing that will detect if chrome developer tools was opened. There's an answer addressing how to do it here https://stackoverflow.com/questions/7798748/find-out-whether-chrome-console-is-open ... but it's hard to say the exact code doing that in your page.. it requires reversing and anyway you probably didn't need to go that far. You should know anyway the client side code can detect it and can behave accordingly — Diego D, May 02 '22 at 11:53
@Archit Gargi if you look at the image I attached, this error occurs only when I open the inspection tool. I tried to open it using VPN but same result — Raisul Islam, May 02 '22 at 13:35
@ArchitGargi Probably because you have an ad blocker or a similar extension in use. — CherryDT, May 02 '22 at 13:46

CherryDT · Accepted Answer · 2022-05-02T14:38:55.817

They are using this DevTools detector. If DevTools are detected, they redirect the player frame to ../player/includes/template/no_video.html:

    <script type="text/javascript">
      !function() {
        navigator.userAgent.match(/Android/i) || navigator.userAgent.match(/webOS/i) || navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i) || navigator.userAgent.match(/iPod/i) || navigator.userAgent.match(/BlackBerry/i) || navigator.userAgent.match(/Windows Phone/i) || (devtoolsDetector.addListener(function(t, e) {
          t && (document.location.href = "../player/includes/template/no_video.html")
        }),
        devtoolsDetector.launch())
      }();
    </script>

You can use some browser extension which is capable of blocking requests and block https://loading.su/player/assets/devtools-detector/devtools-detector.min.js which is where they load the script from. For example, AdBlock Plus configured with "Fanboy's Annoyance List" does successfully block it for me.

Looking at their code, this doesn't happen if a mobile user agent is detected, so what also works is enabling mobile view in DevTools, reloading the page, and then disabling mobile view again while page is already open (because this check is only done once when the video is loaded).

Why 404 error showing if I go to inspection tool?

1 Answers1