diff --git a/src/editor/autocomplete.js b/src/editor/autocomplete.js
index ceaf18c444..92c4db415e 100644
--- a/src/editor/autocomplete.js
+++ b/src/editor/autocomplete.js
@@ -18,12 +18,13 @@ limitations under the License.
 import {UserPillPart, RoomPillPart, PlainPart} from "./parts";
 
 export default class AutocompleteWrapperModel {
-    constructor(updateCallback, getAutocompleterComponent, updateQuery, room) {
+    constructor(updateCallback, getAutocompleterComponent, updateQuery, room, client) {
         this._updateCallback = updateCallback;
         this._getAutocompleterComponent = getAutocompleterComponent;
         this._updateQuery = updateQuery;
         this._query = null;
         this._room = room;
+        this._client = client;
     }
 
     onEscape(e) {
@@ -106,7 +107,7 @@ export default class AutocompleteWrapperModel {
             }
             case "#": {
                 const displayAlias = completion.completionId;
-                return new RoomPillPart(displayAlias);
+                return new RoomPillPart(displayAlias, this._client);
             }
             // also used for emoji completion
             default:
diff --git a/src/editor/deserialize.js b/src/editor/deserialize.js
index 64b219c2a9..48625cba5f 100644
--- a/src/editor/deserialize.js
+++ b/src/editor/deserialize.js
@@ -21,7 +21,7 @@ import { walkDOMDepthFirst } from "./dom";
 
 const REGEX_MATRIXTO = new RegExp(MATRIXTO_URL_PATTERN);
 
-function parseLink(a, room) {
+function parseLink(a, room, client) {
     const {href} = a;
     const pillMatch = REGEX_MATRIXTO.exec(href) || [];
     const resourceId = pillMatch[1]; // The room/user ID
@@ -34,7 +34,7 @@ function parseLink(a, room) {
                 room.getMember(resourceId),
             );
         case "#":
-            return new RoomPillPart(resourceId);
+            return new RoomPillPart(resourceId, client);
         default: {
             if (href === a.textContent) {
                 return new PlainPart(a.textContent);
@@ -57,10 +57,10 @@ function parseCodeBlock(n) {
     return parts;
 }
 
-function parseElement(n, room) {
+function parseElement(n, room, client) {
     switch (n.nodeName) {
         case "A":
-            return parseLink(n, room);
+            return parseLink(n, room, client);
         case "BR":
             return new NewlinePart("\n");
         case "EM":
@@ -140,7 +140,7 @@ function prefixQuoteLines(isFirstNode, parts) {
     }
 }
 
-function parseHtmlMessage(html, room) {
+function parseHtmlMessage(html, room, client) {
     // no nodes from parsing here should be inserted in the document,
     // as scripts in event handlers, etc would be executed then.
     // we're only taking text, so that is fine
@@ -165,7 +165,7 @@ function parseHtmlMessage(html, room) {
         if (n.nodeType === Node.TEXT_NODE) {
             newParts.push(new PlainPart(n.nodeValue));
         } else if (n.nodeType === Node.ELEMENT_NODE) {
-            const parseResult = parseElement(n, room);
+            const parseResult = parseElement(n, room, client);
             if (parseResult) {
                 if (Array.isArray(parseResult)) {
                     newParts.push(...parseResult);
@@ -205,10 +205,10 @@ function parseHtmlMessage(html, room) {
     return parts;
 }
 
-export function parseEvent(event, room) {
+export function parseEvent(event, room, client) {
     const content = event.getContent();
     if (content.format === "org.matrix.custom.html") {
-        return parseHtmlMessage(content.formatted_body || "", room);
+        return parseHtmlMessage(content.formatted_body || "", room, client);
     } else {
         const body = content.body || "";
         const lines = body.split("\n");
diff --git a/src/editor/model.js b/src/editor/model.js
index fb6b417530..a5d2f25f95 100644
--- a/src/editor/model.js
+++ b/src/editor/model.js
@@ -73,7 +73,7 @@ export default class EditorModel {
     }
 
     serializeParts() {
-        return this._parts.map(({type, text}) => {return {type, text};});
+        return this._parts.map(p => p.serialize());
     }
 
     _diff(newValue, inputType, caret) {
diff --git a/src/editor/parts.js b/src/editor/parts.js
index be3080db12..193b35a5ea 100644
--- a/src/editor/parts.js
+++ b/src/editor/parts.js
@@ -102,6 +102,10 @@ class BasePart {
     toString() {
         return `${this.type}(${this.text})`;
     }
+
+    serialize() {
+        return {type: this.type, text: this.text};
+    }
 }
 
 export class PlainPart extends BasePart {
@@ -233,13 +237,12 @@ export class NewlinePart extends BasePart {
 }
 
 export class RoomPillPart extends PillPart {
-    constructor(displayAlias) {
+    constructor(displayAlias, client) {
         super(displayAlias, displayAlias);
-        this._room = this._findRoomByAlias(displayAlias);
+        this._room = this._findRoomByAlias(displayAlias, client);
     }
 
-    _findRoomByAlias(alias) {
-        const client = MatrixClientPeg.get();
+    _findRoomByAlias(alias, client) {
         if (alias[0] === '#') {
             return client.getRooms().find((r) => {
                 return r.getAliases().includes(alias);
@@ -300,6 +303,12 @@ export class UserPillPart extends PillPart {
     get className() {
         return "mx_UserPill mx_Pill";
     }
+
+    serialize() {
+        const obj = super.serialize();
+        obj.userId = this.resourceId;
+        return obj;
+    }
 }
 
 
@@ -335,13 +344,16 @@ export class PillCandidatePart extends PlainPart {
 }
 
 export class PartCreator {
-    constructor(getAutocompleterComponent, updateQuery, room) {
+    constructor(getAutocompleterComponent, updateQuery, room, client) {
+        this._room = room;
+        this._client = client;
         this._autoCompleteCreator = (updateCallback) => {
             return new AutocompleteWrapperModel(
                 updateCallback,
                 getAutocompleterComponent,
                 updateQuery,
                 room,
+                client,
             );
         };
     }
@@ -362,5 +374,22 @@ export class PartCreator {
     createDefaultPart(text) {
         return new PlainPart(text);
     }
+
+    deserializePart(part) {
+        switch (part.type) {
+            case "plain":
+                return new PlainPart(part.text);
+            case "newline":
+                return new NewlinePart(part.text);
+            case "pill-candidate":
+                return new PillCandidatePart(part.text, this._autoCompleteCreator);
+            case "room-pill":
+                return new RoomPillPart(part.text, this._client);
+            case "user-pill": {
+                const member = this._room.getMember(part.userId);
+                return new UserPillPart(part.userId, part.text, member);
+            }
+        }
+    }
 }