For indexed sourcemaps (see parent issue), we can only fix sourcemaps after injection by adjusting the offsets. This is because the indexed sourcemap could contain remote sourcemaps

If the minified source starts with "use […]", we cannot use the method we use with normal sourcemaps, which is to inject after the "use […]". Instead, we will re-inject this "use […]" string before the debug ID code snippet. The string will appear twice in the minified source, but that should be okay, since the source mapping will still work.