diff --git a/packages/playwright-test/src/matchers/golden.ts b/packages/playwright-test/src/matchers/golden.ts
index 1605bb55fe..b7e02ad126 100644
--- a/packages/playwright-test/src/matchers/golden.ts
+++ b/packages/playwright-test/src/matchers/golden.ts
@@ -21,7 +21,7 @@ import fs from 'fs';
 import path from 'path';
 import jpeg from 'jpeg-js';
 import pixelmatch from 'pixelmatch';
-import { diff_match_patch, DIFF_INSERT, DIFF_DELETE, DIFF_EQUAL } from 'playwright-core/src/third_party/diff_match_patch';
+import { diff_match_patch, DIFF_INSERT, DIFF_DELETE, DIFF_EQUAL } from '../third_party/diff_match_patch';
 import { TestInfoImpl, UpdateSnapshots } from '../types';
 import { addSuffixToFilePath } from '../util';
 
diff --git a/packages/playwright-core/src/third_party/diff_match_patch.js b/packages/playwright-test/src/third_party/diff_match_patch.js
similarity index 100%
rename from packages/playwright-core/src/third_party/diff_match_patch.js
rename to packages/playwright-test/src/third_party/diff_match_patch.js
diff --git a/utils/build/build.js b/utils/build/build.js
index 69cd458c01..7080135551 100644
--- a/utils/build/build.js
+++ b/utils/build/build.js
@@ -194,6 +194,13 @@ copyFiles.push({
   ignored: ['**/.eslintrc.js', '**/webpack*.config.js', '**/injected/**/*']
 });
 
+copyFiles.push({
+  files: 'packages/playwright-test/src/**/*.js',
+  from: 'packages/playwright-test/src',
+  to: 'packages/playwright-test/lib',
+  ignored: ['**/.eslintrc.js']
+});
+
 // Sometimes we require JSON files that babel ignores.
 // For example, deviceDescriptorsSource.json
 copyFiles.push({