I've submitted https://github.com/mozilla/pdf.js/pull/10520 upstream, and while it does *not* fix the underlying bug it will at least provide a better fallback behaviour for fonts that are rejected by the sanitizer.
Bug 1524888 Comment 5 Edit History
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I've submitted https://github.com/mozilla/pdf.js/pull/10539 upstream, and while it does *not* fix the underlying bug it will at least provide a better fallback behaviour for fonts that are rejected by the sanitizer.