diff --git a/lib/middleware/karma.js b/lib/middleware/karma.js
index c48332d12..5c3e924f5 100644
--- a/lib/middleware/karma.js
+++ b/lib/middleware/karma.js
@@ -193,7 +193,7 @@ function createKarmaMiddleware (
             } else {
               const scriptType = (SCRIPT_TYPE[fileType] || 'text/javascript')
               const crossOriginAttribute = includeCrossOriginAttribute ? 'crossorigin="anonymous"' : ''
-              scriptTags.push(`<script type="${scriptType}" src="${filePath}" ${crossOriginAttribute}></script>`)
+              scriptTags.push(`<script type="${scriptType}" onerror="throw 'Error loading ${filePath}'" src="${filePath}" ${crossOriginAttribute}></script>`)
             }
           }
 
diff --git a/test/unit/middleware/karma.spec.js b/test/unit/middleware/karma.spec.js
index 16242d09d..9a6a0bdeb 100644
--- a/test/unit/middleware/karma.spec.js
+++ b/test/unit/middleware/karma.spec.js
@@ -207,7 +207,8 @@ describe('middleware.karma', () => {
 
     response.once('end', () => {
       expect(nextSpy).not.to.have.been.called
-      expect(response).to.beServedAs(200, 'CONTEXT\n<script type="text/javascript" src="/__proxy__/__karma__/absolute/first.js?sha123" crossorigin="anonymous"></script>\n<script type="application/dart" src="/__proxy__/__karma__/absolute/second.dart?sha456" crossorigin="anonymous"></script>')
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      expect(response).to.beServedAs(200, `CONTEXT\n<script type="text/javascript" onerror="throw 'Error loading /__proxy__/__karma__/absolute/first.js?sha123'" src="/__proxy__/__karma__/absolute/first.js?sha123" crossorigin="anonymous"></script>\n<script type="application/dart" onerror="throw 'Error loading /__proxy__/__karma__/absolute/second.dart?sha456'" src="/__proxy__/__karma__/absolute/second.dart?sha456" crossorigin="anonymous"></script>`)
       done()
     })
 
@@ -241,7 +242,8 @@ describe('middleware.karma', () => {
 
     response.once('end', () => {
       expect(nextSpy).not.to.have.been.called
-      expect(response).to.beServedAs(200, 'CONTEXT\n<script type="text/javascript" src="/__proxy__/__karma__/absolute/some/abc/a.js?sha" crossorigin="anonymous"></script>\n<script type="text/javascript" src="/__proxy__/__karma__/base/b.js?shaaa" crossorigin="anonymous"></script>')
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      expect(response).to.beServedAs(200, `CONTEXT\n<script type="text/javascript" onerror="throw 'Error loading /__proxy__/__karma__/absolute/some/abc/a.js?sha'" src="/__proxy__/__karma__/absolute/some/abc/a.js?sha" crossorigin="anonymous"></script>\n<script type="text/javascript" onerror="throw 'Error loading /__proxy__/__karma__/base/b.js?shaaa'" src="/__proxy__/__karma__/base/b.js?shaaa" crossorigin="anonymous"></script>`)
       done()
     })
 
@@ -333,7 +335,8 @@ describe('middleware.karma', () => {
     ])
 
     response.once('end', () => {
-      expect(response).to.beServedAs(200, 'CONTEXT\n<script type="text/javascript" src="http://some.url.com/whatever" crossorigin="anonymous"></script>')
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      expect(response).to.beServedAs(200, `CONTEXT\n<script type="text/javascript" onerror="throw 'Error loading http://some.url.com/whatever'" src="http://some.url.com/whatever" crossorigin="anonymous"></script>`)
       done()
     })
 
@@ -366,7 +369,8 @@ describe('middleware.karma', () => {
     ])
 
     response.once('end', () => {
-      expect(response).to.beServedAs(200, "window.__karma__.files = {\n  '/__proxy__/__karma__/absolute/some/abc/a.js': 'sha_a',\n  '/__proxy__/__karma__/base/b.js': 'sha_b',\n  '/__proxy__/__karma__/absolute\\\\windows\\\\path\\\\uuu\\\\c.js': 'sha_c'\n};\n")
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      expect(response).to.beServedAs(200, `window.__karma__.files = {\n  '/__proxy__/__karma__/absolute/some/abc/a.js': 'sha_a',\n  '/__proxy__/__karma__/base/b.js': 'sha_b',\n  '/__proxy__/__karma__/absolute\\\\windows\\\\path\\\\uuu\\\\c.js': 'sha_c'\n};\n`)
       done()
     })
 
@@ -376,7 +380,8 @@ describe('middleware.karma', () => {
   it('should escape quotes in mappings with all served files', (done) => {
     fsMock._touchFile('/karma/static/context.html', 0, '%MAPPINGS%')
     servedFiles([
-      new MockFile("/some/abc/a'b.js", 'sha_a'),
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      new MockFile(`/some/abc/a'b.js`, 'sha_a'),
       new MockFile('/base/path/ba.js', 'sha_b')
     ])
 
@@ -396,7 +401,8 @@ describe('middleware.karma', () => {
 
     response.once('end', () => {
       expect(nextSpy).not.to.have.been.called
-      expect(response).to.beServedAs(200, 'DEBUG\n<script type="text/javascript" src="/__proxy__/__karma__/absolute/first.js" crossorigin="anonymous"></script>\n<script type="text/javascript" src="/__proxy__/__karma__/base/b.js" crossorigin="anonymous"></script>')
+      /* eslint quotes: ["error", "single", { "allowTemplateLiterals": true }] */
+      expect(response).to.beServedAs(200, `DEBUG\n<script type="text/javascript" onerror="throw 'Error loading /__proxy__/__karma__/absolute/first.js'" src="/__proxy__/__karma__/absolute/first.js" crossorigin="anonymous"></script>\n<script type="text/javascript" onerror="throw 'Error loading /__proxy__/__karma__/base/b.js'" src="/__proxy__/__karma__/base/b.js" crossorigin="anonymous"></script>`)
       done()
     })