diff --git a/mix/qml/CodeEditorView.qml b/mix/qml/CodeEditorView.qml
index 01aa0955f..f948f882c 100644
--- a/mix/qml/CodeEditorView.qml
+++ b/mix/qml/CodeEditorView.qml
@@ -67,8 +67,8 @@ Item {
 		return null;
 	}
 
-	function highlightExecution(documentId, location) {
-
+	function highlightExecution(documentId, location)
+	{
 		var editor = getEditor(documentId);
 		if (editor)
 		{
@@ -81,15 +81,12 @@ Item {
 
 	// Execution is not in the current document. Try:
 	// Open targeted document and hightlight (TODO) or
-	// Relevant hightlighting on the current document
+	// Warn user that file is not available
 	function findAndHightlight(start, end, sourceName)
 	{
 		var editor = getEditor(currentDocumentId);
 		if (editor)
-		{
-			var sourceIndex = editor.getText().indexOf(sourceName);
-			highlightExecution(currentDocumentId, { start: sourceIndex, end: sourceIndex + sourceName.length, sourceName: currentDocumentId });
-		}
+			editor.showWarning(qsTr("Currently debugging in " + sourceName + ". Source not available."));
 	}
 
 	function editingContract() {
diff --git a/mix/qml/WebCodeEditor.qml b/mix/qml/WebCodeEditor.qml
index 7e5945fc7..3313cd2dd 100644
--- a/mix/qml/WebCodeEditor.qml
+++ b/mix/qml/WebCodeEditor.qml
@@ -45,6 +45,11 @@ Item {
 			editorBrowser.runJavaScript("highlightExecution(" + location.start + "," + location.end + ")");
 	}
 
+	function showWarning(content) {
+		if (initialized)
+			editorBrowser.runJavaScript("showWarning('" + content + "')");
+	}
+
 	function getBreakpoints() {
 		return currentBreakpoints;
 	}
diff --git a/mix/qml/html/codeeditor.js b/mix/qml/html/codeeditor.js
index daf1286d8..da87e63e0 100644
--- a/mix/qml/html/codeeditor.js
+++ b/mix/qml/html/codeeditor.js
@@ -134,6 +134,8 @@ highlightExecution = function(start, end) {
 		executionMark.clear();
 	if (start === 0 && end + 1 === editor.getValue().length)
 		return; // Do not hightlight the whole document.
+	if (debugWarning)
+		debugWarning.clear();
 	executionMark = editor.markText(editor.posFromIndex(start), editor.posFromIndex(end), { className: "CodeMirror-exechighlight" });
 }
 
@@ -148,6 +150,20 @@ isClean = function()
 	return editor.isClean(changeId);
 }
 
+var debugWarning = null;
+showWarning = function(content)
+{
+	if (executionMark)
+		executionMark.clear();
+	if (debugWarning)
+		debugWarning.clear();
+	var node = document.createElement("div");
+	node.id = "annotation"
+	node.innerHTML = content;
+	node.className = "CodeMirror-errorannotation-context";
+	debugWarning = editor.addLineWidget(0, node, { coverGutter: false, above: true });
+}
+
 var annotation = null;
 var compilationCompleteBool = true;
 compilationError = function(line, column, content)