diff --git a/test/downloadutils.mjs b/test/downloadutils.mjs
index 548e07ecb..ab002c5d3 100644
--- a/test/downloadutils.mjs
+++ b/test/downloadutils.mjs
@@ -110,79 +110,60 @@ function downloadManifestFiles(manifest, callback) {
   downloadNext();
 }
 
-function calculateMD5(file, callback) {
-  var hash = crypto.createHash("md5");
-  var stream = fs.createReadStream(file);
-  stream.on("data", function (data) {
-    hash.update(data);
-  });
-  stream.on("error", function (err) {
-    callback(err);
-  });
-  stream.on("end", function () {
-    var result = hash.digest("hex");
-    callback(null, result);
+function calculateMD5(file) {
+  return new Promise((resolve, reject) => {
+    const hash = crypto.createHash("md5");
+    const stream = fs.createReadStream(file);
+    stream.on("data", data => hash.update(data));
+    stream.on("error", error => reject(error));
+    stream.on("end", () => resolve(hash.digest("hex")));
   });
 }
 
-function verifyManifestFiles(manifest, callback) {
-  function verifyNext() {
-    if (i >= manifest.length) {
-      callback(error);
-      return;
-    }
-    var item = manifest[i];
-    if (fs.existsSync(item.file + ".error")) {
+async function verifyManifestFiles(manifest) {
+  let error = false;
+
+  for (const item of manifest) {
+    if (fs.existsSync(`${item.file}.error`)) {
       console.error(
-        'WARNING: File was not downloaded. See "' + item.file + '.error" file.'
+        `WARNING: "${item.file}" was not downloaded; see "${item.file}.error" file.`
       );
       error = true;
-      i++;
-      verifyNext();
-      return;
+      continue;
     }
-    if (item.link && !fs.existsSync(item.file + ".link")) {
+
+    if (item.link && !fs.existsSync(`${item.file}.link`)) {
       console.error(
         `WARNING: Unneeded \`"link": true\`-entry for the "${item.id}" test.`
       );
       error = true;
-      i++;
-      verifyNext();
-      return;
+      continue;
     }
-    calculateMD5(item.file, function (err, md5) {
-      if (err) {
-        console.log('WARNING: Unable to open file for reading "' + err + '".');
-        error = true;
-      } else if (!item.md5) {
+
+    try {
+      const md5 = await calculateMD5(item.file);
+      if (!item.md5) {
         console.error(
-          'WARNING: Missing md5 for file "' +
-            item.file +
-            '". ' +
-            'Hash for current file is "' +
-            md5 +
-            '"'
+          `WARNING: MD5 hash missing for "${item.file}" (computed "${md5}").`
         );
         error = true;
       } else if (md5 !== item.md5) {
         console.error(
-          'WARNING: MD5 of file "' +
-            item.file +
-            '" does not match file. Expected "' +
-            item.md5 +
-            '" computed "' +
-            md5 +
-            '"'
+          `WARNING: MD5 hash mismatch for "${item.file}" (expected "${item.md5}", computed "${md5}").`
         );
         error = true;
       }
-      i++;
-      verifyNext();
-    });
+    } catch (ex) {
+      console.log(
+        `WARNING: MD5 hash calculation failed for "${item.file}" ("${ex}").`
+      );
+      error = true;
+    }
+  }
+
+  if (error) {
+    throw new Error("Manifest validation failed");
   }
-  var i = 0;
-  var error = false;
-  verifyNext();
 }
 
 export { downloadManifestFiles, verifyManifestFiles };
diff --git a/test/test.mjs b/test/test.mjs
index c24d6e9c3..7095f9a74 100644
--- a/test/test.mjs
+++ b/test/test.mjs
@@ -1071,23 +1071,23 @@ async function closeSession(browser) {
 
 function ensurePDFsDownloaded(callback) {
   var manifest = getTestManifest();
-  downloadManifestFiles(manifest, function () {
-    verifyManifestFiles(manifest, function (hasErrors) {
-      if (hasErrors) {
-        console.log(
-          "Unable to verify the checksum for the files that are " +
-            "used for testing."
-        );
-        console.log(
-          "Please re-download the files, or adjust the MD5 " +
-            "checksum in the manifest for the files listed above.\n"
-        );
-        if (options.strictVerify) {
-          process.exit(1);
-        }
+  downloadManifestFiles(manifest, async function () {
+    try {
+      await verifyManifestFiles(manifest);
+    } catch {
+      console.log(
+        "Unable to verify the checksum for the files that are " +
+          "used for testing."
+      );
+      console.log(
+        "Please re-download the files, or adjust the MD5 " +
+          "checksum in the manifest for the files listed above.\n"
+      );
+      if (options.strictVerify) {
+        process.exit(1);
       }
-      callback();
-    });
+    }
+    callback();
   });
 }