diff --git a/res/css/views/elements/_MessageEditor.scss b/res/css/views/elements/_MessageEditor.scss
index 57ae79da8c..eefb45afe5 100644
--- a/res/css/views/elements/_MessageEditor.scss
+++ b/res/css/views/elements/_MessageEditor.scss
@@ -17,12 +17,28 @@ limitations under the License.
 .mx_MessageEditor {
     border-radius: 4px;
     background-color: #f3f8fd;
-    padding: 10px;
+    padding: 11px 13px 7px 56px;
 
     .editor {
         border-radius: 4px;
         border: solid 1px #e9edf1;
         background-color: #ffffff;
+        padding: 10px;
+
+        span {
+            display: inline-block;
+            padding: 0 5px;
+            border-radius: 4px;
+            color: white;
+        }
+
+        span.user-pill {
+            background: red;
+        }
+
+        span.room-pill {
+            background: green;
+        }
     }
 
     .buttons {
@@ -39,4 +55,12 @@ limitations under the License.
             font-weight: 600;
         }
     }
+
+    .model {
+        background: lightgrey;
+        padding: 5px;
+        display: block;
+        white-space: pre;
+        font-size: 12px;
+    }
 }
diff --git a/src/components/views/elements/MessageEditor.js b/src/components/views/elements/MessageEditor.js
index f57521dbe9..026f92238b 100644
--- a/src/components/views/elements/MessageEditor.js
+++ b/src/components/views/elements/MessageEditor.js
@@ -18,6 +18,9 @@ import sdk from '../../../index';
 import {_t} from '../../../languageHandler';
 import PropTypes from 'prop-types';
 import dis from '../../../dispatcher';
+import EditorModel from '../../../editor/model';
+import {PlainPart} from '../../../editor/parts';
+import {getCaretOffset, setCaretPosition} from '../../../editor/caret';
 import {MatrixEvent, MatrixClient} from 'matrix-js-sdk';
 
 export default class MessageEditor extends React.Component {
@@ -34,8 +37,24 @@ export default class MessageEditor extends React.Component {
 
     constructor(props, context) {
         super(props, context);
-        this.state = {};
+        const body = this.props.event.getContent().body;
+        this.model = new EditorModel();
+        this.model.update(body, undefined, {offset: body.length});
+        this.state = {
+            parts: this.model.serializeParts(),
+        };
         this._onCancelClicked = this._onCancelClicked.bind(this);
+        this._onInput = this._onInput.bind(this);
+    }
+
+    _onInput(event) {
+        const editor = event.target;
+        const caretOffset = getCaretOffset(editor);
+        const caret = this.model.update(editor.textContent, event.inputType, caretOffset);
+        const parts = this.model.serializeParts();
+        this.setState({parts}, () => {
+            setCaretPosition(editor, caret);
+        });
     }
 
     _onCancelClicked() {
@@ -43,14 +62,24 @@ export default class MessageEditor extends React.Component {
     }
 
     render() {
+        const parts = this.state.parts.map((p, i) => {
+            const key = `${i}-${p.type}`;
+            switch (p.type) {
+                case "plain": return p.text;
+                case "room-pill": return (<span key={key} className="room-pill">{p.text}</span>);
+                case "user-pill": return (<span key={key} className="user-pill">{p.text}</span>);
+            }
+        });
+        const modelOutput = JSON.stringify(this.state.parts, undefined, 2);
         const AccessibleButton = sdk.getComponent('elements.AccessibleButton');
         return <div className="mx_MessageEditor">
-                <div className="editor" contentEditable="true">
-                    {this.props.event.getContent().body}
+                <div className="editor" contentEditable="true" tabIndex="1" suppressContentEditableWarning={true} onInput={this._onInput}>
+                    {parts}
                 </div>
                 <div className="buttons">
                     <AccessibleButton onClick={this._onCancelClicked}>{_t("Cancel")}</AccessibleButton>
                 </div>
+                <code className="model">{modelOutput}</code>
             </div>;
     }
 }
diff --git a/src/editor/caret.js b/src/editor/caret.js
index 3b803f35c3..a252ebddc6 100644
--- a/src/editor/caret.js
+++ b/src/editor/caret.js
@@ -14,21 +14,21 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-export function getCaretPosition(editor) {
+export function getCaretOffset(editor) {
     const sel = document.getSelection();
     const atNodeEnd = sel.focusOffset === sel.focusNode.textContent.length;
-    let position = sel.focusOffset;
+    let offset = sel.focusOffset;
     let node = sel.focusNode;
 
     // when deleting the last character of a node,
     // the caret gets reported as being after the focusOffset-th node,
     // with the focusNode being the editor
     if (node === editor) {
-        let position = 0;
+        let offset = 0;
         for (let i = 0; i < sel.focusOffset; ++i) {
-            position += editor.childNodes[i].textContent.length;
+            offset += editor.childNodes[i].textContent.length;
         }
-        return {position, atNodeEnd: false};
+        return {offset, atNodeEnd: false};
     }
 
     // first make sure we're at the level of a direct child of editor
@@ -36,7 +36,7 @@ export function getCaretPosition(editor) {
         // include all preceding siblings of the non-direct editor children
         while (node.previousSibling) {
             node = node.previousSibling;
-            position += node.textContent.length;
+            offset += node.textContent.length;
         }
         // then move up
         // I guess technically there could be preceding text nodes in the parents here as well,
@@ -48,13 +48,13 @@ export function getCaretPosition(editor) {
     // now include the text length of all preceding direct editor children
     while (node.previousSibling) {
         node = node.previousSibling;
-        position += node.textContent.length;
+        offset += node.textContent.length;
     }
-    {
-        const {focusOffset, focusNode} = sel;
-        console.log("selection", {focusOffset, focusNode, position, atNodeEnd});
-    }
-    return {position, atNodeEnd};
+    // {
+    //     const {focusOffset, focusNode} = sel;
+    //     console.log("selection", {focusOffset, focusNode, position, atNodeEnd});
+    // }
+    return {offset, atNodeEnd};
 }
 
 export function setCaretPosition(editor, caretPosition) {
diff --git a/src/editor/model.js b/src/editor/model.js
index ffd2e17c01..b3d6682f79 100644
--- a/src/editor/model.js
+++ b/src/editor/model.js
@@ -40,18 +40,22 @@ export default class EditorModel {
         return this._parts;
     }
 
+    serializeParts() {
+        return this._parts.map(({type, text}) => {return {type, text};});
+    }
+
     _diff(newValue, inputType, caret) {
         if (inputType === "deleteByDrag") {
             return diffDeletion(this._previousValue, newValue);
         } else {
-            return diffAtCaret(this._previousValue, newValue, caret.position);
+            return diffAtCaret(this._previousValue, newValue, caret.offset);
         }
     }
 
     update(newValue, inputType, caret) {
         const diff = this._diff(newValue, inputType, caret);
         const position = this._positionForOffset(diff.at, caret.atNodeEnd);
-        console.log("update at", {position, diff});
+        console.log("update at", {position, diff, newValue, prevValue: this._previousValue});
         if (diff.removed) {
             this._removeText(position, diff.removed.length);
         }