Filtering adblocked requests

Our application makes calls to segment.io that are blocked by ad blockers and we end up with "Failed to fetch" errors in raygun. We'd like to filter these out but it isn't clear to me how to do this using the various filter options.

Is it possible to filter based on the stacktrace of the error? That would be sufficient as there are references to "https://cdn.segment.com/analytics.js" in the stracktrace. Unfortunately the top-level failure message is just "Failed to fetch" and we don't want to filter all of those.