diff --git a/dom/inputmethod/MozKeyboard.js b/dom/inputmethod/MozKeyboard.js
index 7bec21534a5..9f4195ad475 100644
--- a/dom/inputmethod/MozKeyboard.js
+++ b/dom/inputmethod/MozKeyboard.js
@@ -394,6 +394,11 @@ MozInputContext.prototype = {
       return;
     }
 
+    // Update context first before resolving promise to avoid race condition
+    if (json.selectioninfo) {
+      this.updateSelectionContext(json.selectioninfo);
+    }
+
     switch (msg.name) {
       case "Keyboard:SendKey:Result:OK":
         resolver.resolve();
diff --git a/dom/inputmethod/forms.js b/dom/inputmethod/forms.js
index b212a1f8cc8..dfe13e26442 100644
--- a/dom/inputmethod/forms.js
+++ b/dom/inputmethod/forms.js
@@ -224,6 +224,7 @@ let FormAssistant = {
   _documentEncoder: null,
   _editor: null,
   _editing: false,
+  _selectionPrivate: null,
 
   get focusedElement() {
     if (this._focusedElement && Cu.isDeadWrapper(this._focusedElement))
@@ -244,8 +245,6 @@ let FormAssistant = {
       return;
 
     if (this.focusedElement) {
-      this.focusedElement.removeEventListener('mousedown', this);
-      this.focusedElement.removeEventListener('mouseup', this);
       this.focusedElement.removeEventListener('compositionend', this);
       if (this._observer) {
         this._observer.disconnect();
@@ -254,6 +253,10 @@ let FormAssistant = {
       if (!element) {
         this.focusedElement.blur();
       }
+      if (this._selectionPrivate) {
+        this._selectionPrivate.removeSelectionListener(this);
+        this._selectionPrivate = null;
+      }
     }
 
     this._documentEncoder = null;
@@ -269,8 +272,6 @@ let FormAssistant = {
     }
 
     if (element) {
-      element.addEventListener('mousedown', this);
-      element.addEventListener('mouseup', this);
       element.addEventListener('compositionend', this);
       if (isContentEditable(element)) {
         this._documentEncoder = getDocumentEncoder(element);
@@ -280,6 +281,12 @@ let FormAssistant = {
         // Add a nsIEditorObserver to monitor the text content of the focused
         // element.
         this._editor.addEditorObserver(this);
+
+        let selection = this._editor.selection;
+        if (selection) {
+          this._selectionPrivate = selection.QueryInterface(Ci.nsISelectionPrivate);
+          this._selectionPrivate.addSelectionListener(this);
+        }
       }
 
       // If our focusedElement is removed from DOM we want to handle it properly
@@ -305,6 +312,10 @@ let FormAssistant = {
     this.focusedElement = element;
   },
 
+  notifySelectionChanged: function(aDocument, aSelection, aReason) {
+    this.updateSelection();
+  },
+
   get documentEncoder() {
     return this._documentEncoder;
   },
@@ -376,32 +387,6 @@ let FormAssistant = {
         }
         break;
 
-      case 'mousedown':
-         if (!this.focusedElement) {
-          break;
-        }
-
-        // We only listen for this event on the currently focused element.
-        // When the mouse goes down, note the cursor/selection position
-        this.updateSelection();
-        break;
-
-      case 'mouseup':
-        if (!this.focusedElement) {
-          break;
-        }
-
-        // We only listen for this event on the currently focused element.
-        // When the mouse goes up, see if the cursor has moved (or the
-        // selection changed) since the mouse went down. If it has, we
-        // need to tell the keyboard about it
-        range = getSelectionRange(this.focusedElement);
-        if (range[0] !== this.selectionStart ||
-            range[1] !== this.selectionEnd) {
-          this.updateSelection();
-        }
-        break;
-
       case "resize":
         if (!this.isKeyboardOpened)
           return;
@@ -423,25 +408,12 @@ let FormAssistant = {
         }
         break;
 
-      case "input":
-        if (this.focusedElement) {
-          // When the text content changes, notify the keyboard
-          this.updateSelection();
-        }
-        break;
-
       case "keydown":
         if (!this.focusedElement) {
           break;
         }
 
         CompositionManager.endComposition('');
-
-        // We use 'setTimeout' to wait until the input element accomplishes the
-        // change in selection range.
-        content.setTimeout(function() {
-          this.updateSelection();
-        }.bind(this), 0);
         break;
 
       case "keyup":
@@ -450,7 +422,6 @@ let FormAssistant = {
         }
 
         CompositionManager.endComposition('');
-
         break;
 
       case "compositionend":
@@ -525,7 +496,8 @@ let FormAssistant = {
 
         if (json.requestId && doKeypress) {
           sendAsyncMessage("Forms:SendKey:Result:OK", {
-            requestId: json.requestId
+            requestId: json.requestId,
+            selectioninfo: this.getSelectionInfo()
           });
         }
         else if (json.requestId && !doKeypress) {
@@ -583,8 +555,6 @@ let FormAssistant = {
           break;
         }
 
-        this.updateSelection();
-
         if (json.requestId) {
           sendAsyncMessage("Forms:SetSelectionRange:Result:OK", {
             requestId: json.requestId,
@@ -651,6 +621,7 @@ let FormAssistant = {
                                           json.clauses);
         sendAsyncMessage("Forms:SetComposition:Result:OK", {
           requestId: json.requestId,
+          selectioninfo: this.getSelectionInfo()
         });
         break;
       }
@@ -659,6 +630,7 @@ let FormAssistant = {
         CompositionManager.endComposition(json.text);
         sendAsyncMessage("Forms:EndComposition:Result:OK", {
           requestId: json.requestId,
+          selectioninfo: this.getSelectionInfo()
         });
         break;
       }
@@ -757,6 +729,8 @@ let FormAssistant = {
     };
   },
 
+  _selectionTimeout: null,
+
   // Notify when the selection range changes
   updateSelection: function fa_updateSelection() {
     if (!this.focusedElement) {
@@ -764,7 +738,16 @@ let FormAssistant = {
     }
     let selectionInfo = this.getSelectionInfo();
     if (selectionInfo.changed) {
-      sendAsyncMessage("Forms:SelectionChange", this.getSelectionInfo());
+      // A call to setSelectionRange on input field causes 2 selection changes
+      // one to [0,0] and one to actual value. Both are sent in same tick.
+      // Prevent firing two events in that scenario, always only use the last 1
+      if (this._selectionTimeout) {
+        content.clearTimeout(this._selectionTimeout);
+      }
+
+      this._selectionTimeout = content.setTimeout(function() {
+        sendAsyncMessage("Forms:SelectionChange", selectionInfo);
+      });
     }
   }
 };
diff --git a/dom/inputmethod/mochitest/mochitest.ini b/dom/inputmethod/mochitest/mochitest.ini
index 61392de93f4..41bf6ee7156 100644
--- a/dom/inputmethod/mochitest/mochitest.ini
+++ b/dom/inputmethod/mochitest/mochitest.ini
@@ -13,5 +13,6 @@ support-files =
 [test_bug949059.html]
 [test_bug960946.html]
 [test_bug978918.html]
+[test_bug1026997.html]
 [test_delete_focused_element.html]
 [test_sendkey_cancel.html]
diff --git a/dom/inputmethod/mochitest/test_bug1026997.html b/dom/inputmethod/mochitest/test_bug1026997.html
new file mode 100644
index 00000000000..9fa7ef185b8
--- /dev/null
+++ b/dom/inputmethod/mochitest/test_bug1026997.html
@@ -0,0 +1,101 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1026997
+-->
+<head>
+  <title>SelectionChange on InputMethod API.</title>
+  <script type="application/javascript;version=1.7" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript;version=1.7" src="inputmethod_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1026997">Mozilla Bug 1026997</a>
+<p id="display"></p>
+<pre id="test">
+<script class="testbody" type="application/javascript;version=1.7">
+
+inputmethod_setup(function() {
+  runTest();
+});
+
+// The frame script running in file_test_app.html.
+function appFrameScript() {
+  let input = content.document.getElementById('test-input');
+
+  input.focus();
+
+  function next(start, end) {
+    input.setSelectionRange(start, end);
+  }
+
+  addMessageListener("test:KeyBoard:nextSelection", function(event) {
+    let json = event.json;
+    next(json[0], json[1]);
+  });
+}
+
+function runTest() {
+  let actions = [
+    [0, 4],
+    [1, 1],
+    [3, 3],
+    [2, 3]
+  ];
+
+  let counter = 0;
+  let mm = null;
+  let ic = null;
+
+  let im = navigator.mozInputMethod;
+  im.oninputcontextchange = function() {
+    ok(true, 'inputcontextchange event was fired.');
+    im.oninputcontextchange = null;
+
+    ic = im.inputcontext;
+    if (!ic) {
+      ok(false, 'Should have a non-null inputcontext.');
+      inputmethod_cleanup();
+      return;
+    }
+
+    ic.onselectionchange = function() {
+      is(ic.selectionStart, actions[counter][0], "start");
+      is(ic.selectionEnd, actions[counter][1], "end");
+
+      if (++counter === actions.length) {
+        inputmethod_cleanup();
+        return;
+      }
+
+      next();
+    };
+
+    next();
+  };
+
+  // Set current page as an input method.
+  SpecialPowers.wrap(im).setActive(true);
+
+  // Create an app frame to recieve keyboard inputs.
+  let app = document.createElement('iframe');
+  app.src = 'file_test_app.html';
+  app.setAttribute('mozbrowser', true);
+  document.body.appendChild(app);
+  app.addEventListener('mozbrowserloadend', function() {
+    mm = SpecialPowers.getBrowserFrameMessageManager(app);
+    mm.loadFrameScript('data:,(' + appFrameScript.toString() + ')();', false);
+    next();
+  });
+
+  function next() {
+    if (ic && mm) {
+      mm.sendAsyncMessage('test:KeyBoard:nextSelection', actions[counter]);
+    }
+  }
+}
+</script>
+</pre>
+</body>
+</html>
+