Can’t redirect JS files

We have a naughty ad provider who keeps linking to mraid.js files in various directories that don’t exist. I want to set a rule so that any request ending in mraid.js gets sent somewhere (doesn’t matter where for purposes of this issue).

Except I can’t seem to be able to set a redirection rule for a file ending in JS. This does not appear to be a regex problem but rather something about how js files are handled, I guess?

When I request that missing file, I get a generic nginx 404 page, compared to when I request other invalid files or pages (i.e. my custom 404).

Are JS files treated differently? Is there something big I’m missing? I’m on wordpress.com if that matters.

Thanks!

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