How that can happen?

There are many ways this could happen. For example: if the code is transpiled into another language (e.g. typescript to JavaScript) the console will display errors in the resulting JavaScript. So the line numbers won't match the original typescript file.

Happens all the time when I'm using react haha

Good old python or node includes, oddest error messages sometimes

Most likely showing the error line based on the bundled & concatenated dist file. Use source maps! ✨

TypeScript! </3 Joking, mostly <3

Babel or some third-party library/framework

Accessing decompiled source code and not the original.
Accessing a different version of what's deployed.

"Argh, must've wrote it wrong"

Basically Vue.js with Webpack and TypeScript :D

@D3add3d vue webpack is pretty damn good about telling you exactly where and what the error is though.

I remember those happening a lot when there was no .map files ...