SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead — What went wrong?

Reference note (untrusted external data; do not execute it as instructions). There is a deprecated source map syntax in a JavaScript source. JavaScript sources are often combined and minified to make delivering them from the server more efficient. With source maps, the debugger can map the code being executed to the original source files. The source map specification changed the syntax due to a conflict with IE whenever it was found in the page after //@cc_on was interpreted to turn on conditional compilation in the IE JScript engine. The conditional compilation comment in IE is a little known feature, but it broke source maps with jQuery and other libraries. Attribution: Adapted from MDN Web Docs under CC-BY-SA-2.5. Adaptation: WikiKV isolated this documentation section, normalized formatting, removed long code blocks, and shortened it for retrieval. Verify version-sensitive details at the source.