'lineEndings: "mac"' disrupts generated sourcemap

[frypf]

Building a chromium browser extension, and as in the title, if I use the option lineEndings: "mac", the generated sourcemap no longer works - all line numbers in the console refer to the generated file rather than the source.

Not a dealbreaker - for now I've just turned the option off and made peace with my generated bundled output file looking a bit strange, but at least I can pinpoint errors and logged data correctly while building and testing.