404 Error SyntaxError: Unexpected token X in JSON at position 0 at JSON.parse

[Janet Hinkfuss]

We have a custom issue collector that we have used for several years. It stopped working in Chrome several weeks ago. We get the "Oops! Something went wrong..." when clicking on Submit and a 404 error on the POST. Firefox and Edge work fine.

I have Chrome Version 80.0.3987.162.  I believe that we are third-party, self-hosted. We updated the script tags in our HTML file.  Below is browser console and network console output screenshots. I have Googled and found similar issues but not the same. Tried the suggestions to disable plug-ins and clear cache; still get the error. I created a standard issue collector instead of custom and get the same error.

The error is different in Chrome Canary Version 83.0.4101.0; I get an Uncaught TypeError: Cannot read property 'attachment_error' of null.

Chrome browser console error:

Chrome network output:Chrome Canary console error:

[Guido Ehlert]

Hi, it seems, that the problem is solved with Chrome version: 83.0.4103.97

br

Jens

[Janet Hinkfuss]

The issue ended up being browser cache. I had to completely clear cookies and everything from all of history and reboot twice before Chrome started working.