diff --git a/res/css/_components.scss b/res/css/_components.scss
index 36648f4982..6e681894e3 100644
--- a/res/css/_components.scss
+++ b/res/css/_components.scss
@@ -115,6 +115,7 @@
 @import "./views/messages/_MTextBody.scss";
 @import "./views/messages/_MessageActionBar.scss";
 @import "./views/messages/_MessageTimestamp.scss";
+@import "./views/messages/_ReactionDimension.scss";
 @import "./views/messages/_ReactionsRow.scss";
 @import "./views/messages/_ReactionsRowButton.scss";
 @import "./views/messages/_RoomAvatarEvent.scss";
diff --git a/res/css/views/dialogs/_DevtoolsDialog.scss b/res/css/views/dialogs/_DevtoolsDialog.scss
index 815e8408b5..2f01f3ecc6 100644
--- a/res/css/views/dialogs/_DevtoolsDialog.scss
+++ b/res/css/views/dialogs/_DevtoolsDialog.scss
@@ -18,7 +18,12 @@ limitations under the License.
     margin: 10px 0;
 }
 
-.mx_DevTools_RoomStateExplorer_button, .mx_DevTools_RoomStateExplorer_query {
+.mx_DevTools_ServersInRoomList_button {
+    /* Set the cursor back to default as `.mx_Dialog button` sets it to pointer */
+    cursor: default !important;
+}
+
+.mx_DevTools_RoomStateExplorer_button, .mx_DevTools_ServersInRoomList_button, .mx_DevTools_RoomStateExplorer_query {
     margin-bottom: 10px;
     width: 100%;
 }
diff --git a/res/css/views/messages/_MessageActionBar.scss b/res/css/views/messages/_MessageActionBar.scss
index 877e1916fc..419542036e 100644
--- a/res/css/views/messages/_MessageActionBar.scss
+++ b/res/css/views/messages/_MessageActionBar.scss
@@ -72,13 +72,3 @@ limitations under the License.
 .mx_MessageActionBar_optionsButton::after {
     mask-image: url('$(res)/img/icon_context.svg');
 }
-
-.mx_MessageActionBar_reactionDimension {
-    width: 42px;
-    display: flex;
-    justify-content: space-evenly;
-}
-
-.mx_MessageActionBar_reactionDisabled {
-    opacity: 0.4;
-}
diff --git a/res/css/views/messages/_ReactionDimension.scss b/res/css/views/messages/_ReactionDimension.scss
new file mode 100644
index 0000000000..9a891d05cf
--- /dev/null
+++ b/res/css/views/messages/_ReactionDimension.scss
@@ -0,0 +1,25 @@
+/*
+Copyright 2019 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+.mx_ReactionDimension {
+    width: 42px;
+    display: flex;
+    justify-content: space-evenly;
+}
+
+.mx_ReactionDimension_disabled {
+    opacity: 0.4;
+}
diff --git a/src/components/structures/RoomView.js b/src/components/structures/RoomView.js
index 99f13dcd35..5f4dc984d0 100644
--- a/src/components/structures/RoomView.js
+++ b/src/components/structures/RoomView.js
@@ -40,7 +40,7 @@ import dis from '../../dispatcher';
 import Tinter from '../../Tinter';
 import rate_limited_func from '../../ratelimitedfunc';
 import ObjectUtils from '../../ObjectUtils';
-import Rooms from '../../Rooms';
+import * as Rooms from '../../Rooms';
 
 import { KeyCode, isOnlyCtrlOrCmdKeyEvent } from '../../Keyboard';
 
diff --git a/src/components/views/dialogs/DevtoolsDialog.js b/src/components/views/dialogs/DevtoolsDialog.js
index 3db516a74d..0835c41bb9 100644
--- a/src/components/views/dialogs/DevtoolsDialog.js
+++ b/src/components/views/dialogs/DevtoolsDialog.js
@@ -551,11 +551,53 @@ class AccountDataExplorer extends DevtoolsComponent {
     }
 }
 
+class ServersInRoomList extends DevtoolsComponent {
+    static getLabel() { return _t('View Servers in Room'); }
+
+    static propTypes = {
+        onBack: PropTypes.func.isRequired,
+    };
+
+    constructor(props, context) {
+        super(props, context);
+
+        const room = MatrixClientPeg.get().getRoom(this.context.roomId);
+        const servers = new Set();
+        room.currentState.getStateEvents("m.room.member").forEach(ev => servers.add(ev.getSender().split(":")[1]));
+        this.servers = Array.from(servers).map(s =>
+            <button key={s} className="mx_DevTools_ServersInRoomList_button">
+                { s }
+            </button>);
+
+        this.state = {
+            query: '',
+        };
+    }
+
+    onQuery = (query) => {
+        this.setState({ query });
+    }
+
+    render() {
+        return <div>
+            <div className="mx_Dialog_content">
+                <FilteredList query={this.state.query} onChange={this.onQuery}>
+                    { this.servers }
+                </FilteredList>
+            </div>
+            <div className="mx_Dialog_buttons">
+                <button onClick={this.props.onBack}>{ _t('Back') }</button>
+            </div>
+        </div>;
+    }
+}
+
 const Entries = [
     SendCustomEvent,
     RoomStateExplorer,
     SendAccountData,
     AccountDataExplorer,
+    ServersInRoomList,
 ];
 
 export default class DevtoolsDialog extends React.Component {
diff --git a/src/components/views/messages/MessageActionBar.js b/src/components/views/messages/MessageActionBar.js
index 74eb4165e9..9a482c9e6e 100644
--- a/src/components/views/messages/MessageActionBar.js
+++ b/src/components/views/messages/MessageActionBar.js
@@ -16,7 +16,6 @@ limitations under the License.
 
 import React from 'react';
 import PropTypes from 'prop-types';
-import classNames from 'classnames';
 
 import { _t } from '../../../languageHandler';
 import sdk from '../../../index';
@@ -35,15 +34,6 @@ export default class MessageActionBar extends React.PureComponent {
         onFocusChange: PropTypes.func,
     };
 
-    constructor(props) {
-        super(props);
-
-        this.state = {
-            agreeDimension: null,
-            likeDimension: null,
-        };
-    }
-
     onFocusChange = (focused) => {
         if (!this.props.onFocusChange) {
             return;
@@ -59,31 +49,6 @@ export default class MessageActionBar extends React.PureComponent {
         );
     }
 
-    onAgreeClick = (ev) => {
-        this.toggleDimensionValue("agreeDimension", "agree");
-    }
-
-    onDisagreeClick = (ev) => {
-        this.toggleDimensionValue("agreeDimension", "disagree");
-    }
-
-    onLikeClick = (ev) => {
-        this.toggleDimensionValue("likeDimension", "like");
-    }
-
-    onDislikeClick = (ev) => {
-        this.toggleDimensionValue("likeDimension", "dislike");
-    }
-
-    toggleDimensionValue(dimension, value) {
-        const state = this.state[dimension];
-        const newState = state !== value ? value : null;
-        this.setState({
-            [dimension]: newState,
-        });
-        // TODO: Send the reaction event
-    }
-
     onReplyClick = (ev) => {
         dis.dispatch({
             action: 'reply_to_event',
@@ -134,25 +99,21 @@ export default class MessageActionBar extends React.PureComponent {
             return null;
         }
 
-        const state = this.state.agreeDimension;
+        const ReactionDimension = sdk.getComponent('messages.ReactionDimension');
         const options = [
             {
                 key: "agree",
                 content: "👍",
-                onClick: this.onAgreeClick,
             },
             {
                 key: "disagree",
                 content: "👎",
-                onClick: this.onDisagreeClick,
             },
         ];
-
-        return <span className="mx_MessageActionBar_reactionDimension"
+        return <ReactionDimension
             title={_t("Agree or Disagree")}
-        >
-            {this.renderReactionDimensionItems(state, options)}
-        </span>;
+            options={options}
+        />;
     }
 
     renderLikeDimension() {
@@ -160,40 +121,21 @@ export default class MessageActionBar extends React.PureComponent {
             return null;
         }
 
-        const state = this.state.likeDimension;
+        const ReactionDimension = sdk.getComponent('messages.ReactionDimension');
         const options = [
             {
                 key: "like",
                 content: "🙂",
-                onClick: this.onLikeClick,
             },
             {
                 key: "dislike",
                 content: "😔",
-                onClick: this.onDislikeClick,
             },
         ];
-
-        return <span className="mx_MessageActionBar_reactionDimension"
+        return <ReactionDimension
             title={_t("Like or Dislike")}
-        >
-            {this.renderReactionDimensionItems(state, options)}
-        </span>;
-    }
-
-    renderReactionDimensionItems(state, options) {
-        return options.map(option => {
-            const disabled = state && state !== option.key;
-            const classes = classNames({
-                mx_MessageActionBar_reactionDisabled: disabled,
-            });
-            return <span key={option.key}
-                className={classes}
-                onClick={option.onClick}
-            >
-                {option.content}
-            </span>;
-        });
+            options={options}
+        />;
     }
 
     render() {
diff --git a/src/components/views/messages/ReactionDimension.js b/src/components/views/messages/ReactionDimension.js
new file mode 100644
index 0000000000..3b72aabe15
--- /dev/null
+++ b/src/components/views/messages/ReactionDimension.js
@@ -0,0 +1,73 @@
+/*
+Copyright 2019 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from 'react';
+import PropTypes from 'prop-types';
+import classNames from 'classnames';
+
+export default class ReactionDimension extends React.PureComponent {
+    static propTypes = {
+        options: PropTypes.array.isRequired,
+        title: PropTypes.string,
+    };
+
+    constructor(props) {
+        super(props);
+
+        this.state = {
+            selected: null,
+        };
+    }
+
+    onOptionClick = (ev) => {
+        const { key } = ev.target.dataset;
+        this.toggleDimensionValue(key);
+    }
+
+    toggleDimensionValue(value) {
+        const state = this.state.selected;
+        const newState = state !== value ? value : null;
+        this.setState({
+            selected: newState,
+        });
+        // TODO: Send the reaction event
+    }
+
+    render() {
+        const { selected } = this.state;
+        const { options } = this.props;
+
+        const items = options.map(option => {
+            const disabled = selected && selected !== option.key;
+            const classes = classNames({
+                mx_ReactionDimension_disabled: disabled,
+            });
+            return <span key={option.key}
+                data-key={option.key}
+                className={classes}
+                onClick={this.onOptionClick}
+            >
+                {option.content}
+            </span>;
+        });
+
+        return <span className="mx_ReactionDimension"
+            title={this.props.title}
+        >
+            {items}
+        </span>;
+    }
+}
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index 640f31c1a7..d396c70e4c 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -1133,6 +1133,7 @@
     "Filter results": "Filter results",
     "Explore Room State": "Explore Room State",
     "Explore Account Data": "Explore Account Data",
+    "View Servers in Room": "View Servers in Room",
     "Toolbox": "Toolbox",
     "Developer Tools": "Developer Tools",
     "An error has occurred.": "An error has occurred.",