diff --git a/src/adapter.js b/src/adapter.js
index 9218b59..278e7fe 100644
--- a/src/adapter.js
+++ b/src/adapter.js
@@ -60,13 +60,24 @@ function getRelevantStackFrom (stack) {
  * @return {String}      Formatted step.
  */
 function formatFailedStep (step) {
-  // Safari seems to have no stack trace,
-  // so we just return the error message:
-  if (!step.stack) { return step.message }
-
   var relevantMessage = []
   var relevantStack = []
 
+  // Safari/Firefox seems to have no stack trace,
+  // so we just return the error message and if available
+  // construct a stacktrace out of filename and lineno:
+  if (!step.stack) {
+    if (step.filename) {
+      let stackframe = step.filename
+      if (step.lineno) {
+        stackframe = stackframe + ':' + step.lineno
+      }
+      relevantStack.push(stackframe)
+    }
+    relevantMessage.push(step.message)
+    return relevantMessage.concat(relevantStack).join('\n')
+  }
+
   // Remove the message prior to processing the stack to prevent issues like
   // https://github.com/karma-runner/karma-jasmine/issues/79
   var stack = step.stack.replace('Error: ' + step.message, '')
diff --git a/test/adapter.spec.js b/test/adapter.spec.js
index cc54f44..1d4370e 100644
--- a/test/adapter.spec.js
+++ b/test/adapter.spec.js
@@ -335,6 +335,16 @@ describe('jasmine adapter', function () {
       expect(formatFailedStep(step)).toBe('MESSAGE')
     })
 
+    it('should report message, filename and linenumber if no stack trace but filename and lineno', function () {
+      var step = {
+        passed: false,
+        lineno: 45,
+        filename: 'source/controller.js',
+        message: 'MESSAGE'
+      }
+
+      expect(formatFailedStep(step)).toBe('MESSAGE\nsource/controller.js:45')
+    })
     it('should properly format message containing new-line characters', function () {
       // FF does not have the message in the stack trace