The prebuilt files include `web/pdf_viewer.js` with some viewer APIs. Those are missing from type declarations.
gulp.series(setTestEnv, "generic", function runIntegrationTest() {
    return createTestSource("integration");
  })
);
gulp.task(
  "fonttest",
  gulp.series(setTestEnv, function runFontTest() {
    return createTestSource("font");
  })
);
gulp.task(
  "makeref",
  gulp.series(setTestEnv, "generic", "components", function runMakeref(done) {
    makeRef(done);
  })
);
gulp.task(
  "botmakeref",
  gulp.series(
    setTestEnv,
    "generic",
    "components",
    function runBotMakeref(done) {
      makeRef(done, true);
    }
  )
);
gulp.task(
  "typestest",
  gulp.series(