TrackJS JavaScript Answers

Generic browser error when cross-origin scripts fail. Caused by Same-Origin Policy blocking error details from external scripts. Quick fixes: add crossorigin attribute, enable CORS headers, check CSP settings.

Browser warning when ResizeObserver callbacks cause layout changes. Usually harmless but can indicate performance issues. Quick fixes: check for infinite resize loops, review callback logic, monitor frequency.

Firefox displays this error when fetch requests encounter connection problems. Often caused by blocked requests, CORS violations, or unreachable servers. Quick fixes: inspect console, verify endpoints, check browser settings.

Safari shows "Load failed" when fetch requests can't connect to servers. Common causes include network issues, CORS problems, or server downtime. Quick fixes: verify URL, check network connection, test in other browsers.

Chromium browsers show "Failed to fetch" when requests get no response. Usually CORS issues, ad blockers, or URL typos. Quick fixes: check URL, test in new tab, disable ad blockers.

Starting in April of 2024, lots of websites that use TrackJS (as well as other vendors) started getting large volumes of this error:, Object Not Found Matching Id:1, MethodName:update, ParamCount:4.

We’ll often run into errors like “Cannot read properties of undefined (reading ‘id’)”. It’s one of the most common errors that developers encounter during web development. Let’s dig in and understand this error, what it means, and how we can debug it.

One of the most common errors we record, “Cannot read properties of undefined (reading ‘length’)”, turned up in our own logs recently while looking into an issue with Microsoft Edge and the Facebook sdk. Let’s dive into this error, what it means, and how to fix it.

We ran into a scary looking error message in the Chrome console, Refused to get unsafe header "TrackJS-Correlation-Id". Our code was trying to read this header from a request, so it looked like something real, except that other than the error message, everything was working fine. Let’s explore what was happening and how we fixed it.

HTML Forms have some really strange JavaScript behavior. We’ll often want to add JavaScript to enhance form controls and actions, but sometimes weird things happen, like the submit function disappearing.