That is the not-identical / strict-inequality operator

It is written like so: !==

It returns true if the operands are different in value or type.

The reason it looks like it does in your editor is because you have font ligatures turned on. Font ligatures may look nice, but they create exactly this problem: they disguise the actual characters of the source code, leading to confusion.

VS Code lets you turn them off, and you should. Go to settings and search for "ligatures".