diff --git a/src/components/views/dialogs/AddExistingToSpaceDialog.tsx b/src/components/views/dialogs/AddExistingToSpaceDialog.tsx
index 822ffc2827..8997e4a5f8 100644
--- a/src/components/views/dialogs/AddExistingToSpaceDialog.tsx
+++ b/src/components/views/dialogs/AddExistingToSpaceDialog.tsx
@@ -39,6 +39,9 @@ import ProgressBar from "../elements/ProgressBar";
 import {SpaceFeedbackPrompt} from "../../structures/SpaceRoomView";
 import DecoratedRoomAvatar from "../avatars/DecoratedRoomAvatar";
 import QueryMatcher from "../../../autocomplete/QueryMatcher";
+import TruncatedList from "../elements/TruncatedList";
+import EntityTile from "../rooms/EntityTile";
+import BaseAvatar from "../avatars/BaseAvatar";
 
 interface IProps extends IDialogProps {
     matrixClient: MatrixClient;
@@ -204,6 +207,17 @@ export const AddExistingToSpace: React.FC<IAddExistingToSpaceProps> = ({
         setSelectedToAdd(new Set(selectedToAdd));
     } : null;
 
+    const [truncateAt, setTruncateAt] = useState(20);
+    function overflowTile(overflowCount, totalCount) {
+        const text = _t("and %(count)s others...", { count: overflowCount });
+        return (
+            <EntityTile className="mx_EntityTile_ellipsis" avatarJsx={
+                <BaseAvatar url={require("../../../../res/img/ellipsis.svg")} name="..." width={36} height={36} />
+            } name={text} presenceState="online" suppressOnHover={true}
+            onClick={() => setTruncateAt(totalCount)} />
+        );
+    }
+
     return <div className="mx_AddExistingToSpace">
         <SearchBox
             className="mx_textinput_icon mx_textinput_search"
@@ -216,16 +230,21 @@ export const AddExistingToSpace: React.FC<IAddExistingToSpaceProps> = ({
             { rooms.length > 0 ? (
                 <div className="mx_AddExistingToSpace_section">
                     <h3>{ _t("Rooms") }</h3>
-                    { rooms.map(room => {
-                        return <Entry
-                            key={room.roomId}
-                            room={room}
-                            checked={selectedToAdd.has(room)}
-                            onChange={onChange ? (checked) => {
-                                onChange(checked, room);
-                            } : null}
-                        />;
-                    }) }
+                    <TruncatedList
+                        truncateAt={truncateAt}
+                        createOverflowElement={overflowTile}
+                        getChildren={(start, end) => rooms.slice(start, end).map(room =>
+                            <Entry
+                                key={room.roomId}
+                                room={room}
+                                checked={selectedToAdd.has(room)}
+                                onChange={onChange ? (checked) => {
+                                    onChange(checked, room);
+                                } : null}
+                            />,
+                        )}
+                        getChildCount={() => rooms.length}
+                    />
                 </div>
             ) : undefined }
 
diff --git a/src/components/views/dialogs/ForwardDialog.tsx b/src/components/views/dialogs/ForwardDialog.tsx
index 6fbed6fc8b..ba06436ae2 100644
--- a/src/components/views/dialogs/ForwardDialog.tsx
+++ b/src/components/views/dialogs/ForwardDialog.tsx
@@ -40,6 +40,9 @@ import NotificationBadge from "../rooms/NotificationBadge";
 import { RoomPermalinkCreator } from "../../../utils/permalinks/Permalinks";
 import { sortRooms } from "../../../stores/room-list/algorithms/tag-sorting/RecentAlgorithm";
 import QueryMatcher from "../../../autocomplete/QueryMatcher";
+import TruncatedList from "../elements/TruncatedList";
+import EntityTile from "../rooms/EntityTile";
+import BaseAvatar from "../avatars/BaseAvatar";
 
 const AVATAR_SIZE = 30;
 
@@ -196,6 +199,17 @@ const ForwardDialog: React.FC<IProps> = ({ matrixClient: cli, event, permalinkCr
         }).match(lcQuery);
     }
 
+    const [truncateAt, setTruncateAt] = useState(20);
+    function overflowTile(overflowCount, totalCount) {
+        const text = _t("and %(count)s others...", { count: overflowCount });
+        return (
+            <EntityTile className="mx_EntityTile_ellipsis" avatarJsx={
+                <BaseAvatar url={require("../../../../res/img/ellipsis.svg")} name="..." width={36} height={36} />
+            } name={text} presenceState="online" suppressOnHover={true}
+            onClick={() => setTruncateAt(totalCount)} />
+        );
+    }
+
     return <BaseDialog
         title={_t("Forward message")}
         className="mx_ForwardDialog"
@@ -228,15 +242,20 @@ const ForwardDialog: React.FC<IProps> = ({ matrixClient: cli, event, permalinkCr
             <AutoHideScrollbar className="mx_ForwardList_content">
                 { rooms.length > 0 ? (
                     <div className="mx_ForwardList_results">
-                        { rooms.map(room =>
-                            <Entry
-                                key={room.roomId}
-                                room={room}
-                                event={event}
-                                matrixClient={cli}
-                                onFinished={onFinished}
-                            />,
-                        ) }
+                        <TruncatedList
+                            truncateAt={truncateAt}
+                            createOverflowElement={overflowTile}
+                            getChildren={(start, end) => rooms.slice(start, end).map(room =>
+                                <Entry
+                                    key={room.roomId}
+                                    room={room}
+                                    event={event}
+                                    matrixClient={cli}
+                                    onFinished={onFinished}
+                                />,
+                            )}
+                            getChildCount={() => rooms.length}
+                        />
                     </div>
                 ) : <span className="mx_ForwardList_noResults">
                     { _t("No results") }
diff --git a/src/components/views/elements/TruncatedList.js b/src/components/views/elements/TruncatedList.tsx
similarity index 65%
rename from src/components/views/elements/TruncatedList.js
rename to src/components/views/elements/TruncatedList.tsx
index 0509775545..395caa9222 100644
--- a/src/components/views/elements/TruncatedList.js
+++ b/src/components/views/elements/TruncatedList.tsx
@@ -16,31 +16,29 @@ limitations under the License.
 */
 
 import React from 'react';
-import PropTypes from 'prop-types';
 import { _t } from '../../../languageHandler';
 import {replaceableComponent} from "../../../utils/replaceableComponent";
 
-@replaceableComponent("views.elements.TruncatedList")
-export default class TruncatedList extends React.Component {
-    static propTypes = {
-        // The number of elements to show before truncating. If negative, no truncation is done.
-        truncateAt: PropTypes.number,
-        // The className to apply to the wrapping div
-        className: PropTypes.string,
-        // A function that returns the children to be rendered into the element.
-        // function getChildren(start: number, end: number): Array<React.Node>
-        // The start element is included, the end is not (as in `slice`).
-        // If omitted, the React child elements will be used. This parameter can be used
-        // to avoid creating unnecessary React elements.
-        getChildren: PropTypes.func,
-        // A function that should return the total number of child element available.
-        // Required if getChildren is supplied.
-        getChildCount: PropTypes.func,
-        // A function which will be invoked when an overflow element is required.
-        // This will be inserted after the children.
-        createOverflowElement: PropTypes.func,
-    };
+interface IProps {
+    // The number of elements to show before truncating. If negative, no truncation is done.
+    truncateAt?: number;
+    // The className to apply to the wrapping div
+    className?: string;
+    // A function that returns the children to be rendered into the element.
+    // The start element is included, the end is not (as in `slice`).
+    // If omitted, the React child elements will be used. This parameter can be used
+    // to avoid creating unnecessary React elements.
+    getChildren?: (start: number, end: number) => Array<React.ReactNode>;
+    // A function that should return the total number of child element available.
+    // Required if getChildren is supplied.
+    getChildCount?: () => number;
+    // A function which will be invoked when an overflow element is required.
+    // This will be inserted after the children.
+    createOverflowElement?: (overflowCount: number, totalCount: number) => React.ReactNode;
+}
 
+@replaceableComponent("views.elements.TruncatedList")
+export default class TruncatedList extends React.Component<IProps> {
     static defaultProps ={
         truncateAt: 2,
         createOverflowElement(overflowCount, totalCount) {
@@ -50,7 +48,7 @@ export default class TruncatedList extends React.Component {
         },
     };
 
-    _getChildren(start, end) {
+    private getChildren(start: number, end: number): Array<React.ReactNode> {
         if (this.props.getChildren && this.props.getChildCount) {
             return this.props.getChildren(start, end);
         } else {
@@ -63,7 +61,7 @@ export default class TruncatedList extends React.Component {
         }
     }
 
-    _getChildCount() {
+    private getChildCount(): number {
         if (this.props.getChildren && this.props.getChildCount) {
             return this.props.getChildCount();
         } else {
@@ -73,10 +71,10 @@ export default class TruncatedList extends React.Component {
         }
     }
 
-    render() {
+    public render() {
         let overflowNode = null;
 
-        const totalChildren = this._getChildCount();
+        const totalChildren = this.getChildCount();
         let upperBound = totalChildren;
         if (this.props.truncateAt >= 0) {
             const overflowCount = totalChildren - this.props.truncateAt;
@@ -87,7 +85,7 @@ export default class TruncatedList extends React.Component {
                 upperBound = this.props.truncateAt;
             }
         }
-        const childNodes = this._getChildren(0, upperBound);
+        const childNodes = this.getChildren(0, upperBound);
 
         return (
             <div className={this.props.className}>