diff --git a/res/css/_components.scss b/res/css/_components.scss
index 6f66a8c15e..4fb0eed4af 100644
--- a/res/css/_components.scss
+++ b/res/css/_components.scss
@@ -95,6 +95,7 @@
 @import "./views/elements/_SyntaxHighlight.scss";
 @import "./views/elements/_ToggleSwitch.scss";
 @import "./views/elements/_ToolTipButton.scss";
+@import "./views/elements/_Tooltip.scss";
 @import "./views/globals/_MatrixToolbar.scss";
 @import "./views/groups/_GroupPublicityToggle.scss";
 @import "./views/groups/_GroupRoomList.scss";
@@ -137,7 +138,6 @@
 @import "./views/rooms/_RoomPreviewBar.scss";
 @import "./views/rooms/_RoomRecoveryReminder.scss";
 @import "./views/rooms/_RoomTile.scss";
-@import "./views/rooms/_RoomTooltip.scss";
 @import "./views/rooms/_RoomUpgradeWarningBar.scss";
 @import "./views/rooms/_SearchBar.scss";
 @import "./views/rooms/_SearchableEntityList.scss";
diff --git a/res/css/views/elements/_Field.scss b/res/css/views/elements/_Field.scss
index 4a74262fd4..22bc6a1800 100644
--- a/res/css/views/elements/_Field.scss
+++ b/res/css/views/elements/_Field.scss
@@ -141,6 +141,39 @@ limitations under the License.
     color: $greyed-fg-color;
 }
 
+.mx_Field_valid input,
+.mx_Field_valid select,
+.mx_Field_valid textarea {
+    border-color: $input-valid-border-color ! important;
+}
+
+.mx_Field_valid input + label,
+.mx_Field_valid select + label,
+.mx_Field_valid textarea + label {
+    color: $input-valid-border-color ! important;
+}
+
+.mx_Field_invalid input,
+.mx_Field_invalid select,
+.mx_Field_invalid textarea {
+    border-color: $input-invalid-border-color ! important;
+}
+
+.mx_Field_invalid input + label,
+.mx_Field_invalid select + label,
+.mx_Field_invalid textarea + label {
+    color: $input-invalid-border-color ! important;
+}
+
+.mx_Field_tooltip {
+    margin-top: -12px;
+    margin-left: 4px;
+}
+
+.mx_Field_tooltip.mx_Field_valid {
+    animation: mx_fadeout 1s 2s forwards;
+}
+
 // Customise other components when placed inside a Field
 
 .mx_Field .mx_Dropdown_input {
diff --git a/res/css/views/rooms/_RoomTooltip.scss b/res/css/views/elements/_Tooltip.scss
similarity index 54%
rename from res/css/views/rooms/_RoomTooltip.scss
rename to res/css/views/elements/_Tooltip.scss
index 295786d2d3..78604b1564 100644
--- a/res/css/views/rooms/_RoomTooltip.scss
+++ b/res/css/views/elements/_Tooltip.scss
@@ -1,5 +1,6 @@
 /*
 Copyright 2015, 2016 OpenMarket Ltd
+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.
@@ -14,41 +15,55 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-.mx_RoomTooltip_chevron {
-    position: absolute;
-    left: -8px;
-    top: 4px;
-    width: 0;
-    height: 0;
-    border-top: 8px solid transparent;
-    border-right: 8px solid $menu-bg-color;
-    border-bottom: 8px solid transparent;
+@keyframes mx_fadein {
+    from { opacity: 0; }
+    to { opacity: 1; }
 }
 
-.mx_RoomTooltip_chevron:after {
-    content:'';
+@keyframes mx_fadeout {
+    from { opacity: 1; }
+    to { opacity: 0; }
+}
+
+.mx_Tooltip_chevron {
+    position: absolute;
+    left: -7px;
+    top: 10px;
     width: 0;
     height: 0;
     border-top: 7px solid transparent;
-    border-right: 7px solid $primary-bg-color;
+    border-right: 7px solid $menu-border-color;
     border-bottom: 7px solid transparent;
-    position:absolute;
-    top: -7px;
+}
+
+.mx_Tooltip_chevron:after {
+    content:'';
+    width: 0;
+    height: 0;
+    border-top: 6px solid transparent;
+    border-right: 6px solid $menu-bg-color;
+    border-bottom: 6px solid transparent;
+    position: absolute;
+    top: -6px;
     left: 1px;
 }
 
-.mx_RoomTooltip {
+.mx_Tooltip {
     display: none;
+    animation: mx_fadein 0.2s;
     position: fixed;
-    border-radius: 5px;
-    box-shadow: 0 0 5px 0 rgba(0, 0, 0, 0.21);
-    background-color: $primary-bg-color;
+    border: 1px solid $menu-border-color;
+    border-radius: 4px;
+    box-shadow: 4px 4px 12px 0 rgba(118, 131, 156, 0.6);
+    background-color: $menu-bg-color;
     z-index: 2000;
-    padding: 5px;
+    padding: 10px;
     pointer-events: none;
     line-height: 14px;
-    font-size: 13px;
+    font-size: 12px;
+    font-weight: 600;
     color: $primary-fg-color;
-    max-width: 600px;
+    max-width: 200px;
+    word-break: break-word;
     margin-right: 50px;
 }
diff --git a/res/themes/dark/css/_dark.scss b/res/themes/dark/css/_dark.scss
index deed7235cb..3112644a73 100644
--- a/res/themes/dark/css/_dark.scss
+++ b/res/themes/dark/css/_dark.scss
@@ -53,6 +53,7 @@ $input-lighter-bg-color: #f2f5f8;
 $input-lighter-fg-color: $input-darker-fg-color;
 $input-focused-border-color: #238cf5;
 $input-valid-border-color: $accent-color;
+$input-invalid-border-color: $warning-color;
 
 $field-focused-label-bg-color: $bg-color;
 
diff --git a/res/themes/light/css/_light.scss b/res/themes/light/css/_light.scss
index 4d8e4fa40e..879be67dda 100644
--- a/res/themes/light/css/_light.scss
+++ b/res/themes/light/css/_light.scss
@@ -79,6 +79,7 @@ $input-lighter-bg-color: #f2f5f8;
 $input-lighter-fg-color: $input-darker-fg-color;
 $input-focused-border-color: #238cf5;
 $input-valid-border-color: $accent-color;
+$input-invalid-border-color: $warning-color;
 
 $field-focused-label-bg-color: #ffffff;
 
@@ -95,7 +96,7 @@ $input-fg-color: rgba(74, 74, 74, 0.9);
 $scrollbar-thumb-color: rgba(0, 0, 0, 0.2);
 $scrollbar-track-color: transparent;
 // context menus
-$menu-border-color: #ebedf8;
+$menu-border-color: #e7e7e7;
 $menu-bg-color: #fff;
 $menu-box-shadow-color: rgba(118, 131, 156, 0.6);
 $menu-selected-color: #f5f8fa;
diff --git a/src/components/structures/BottomLeftMenu.js b/src/components/structures/BottomLeftMenu.js
index 47b30be450..2f48bd0299 100644
--- a/src/components/structures/BottomLeftMenu.js
+++ b/src/components/structures/BottomLeftMenu.js
@@ -145,8 +145,8 @@ module.exports = React.createClass({
     // Get the label/tooltip to show
     getLabel: function(label, show) {
         if (show) {
-            const RoomTooltip = sdk.getComponent("rooms.RoomTooltip");
-            return <RoomTooltip className="mx_BottomLeftMenu_tooltip" label={label} />;
+            const Tooltip = sdk.getComponent("elements.Tooltip");
+            return <Tooltip className="mx_BottomLeftMenu_tooltip" label={label} />;
         }
     },
 
diff --git a/src/components/views/auth/ServerConfig.js b/src/components/views/auth/ServerConfig.js
index cb0e0dc38e..ed6b4bdf7d 100644
--- a/src/components/views/auth/ServerConfig.js
+++ b/src/components/views/auth/ServerConfig.js
@@ -90,6 +90,15 @@ export default class ServerConfig extends React.PureComponent {
         this.setState({ hsUrl });
     }
 
+    onHomeserverValidate = (value) => {
+        try {
+            new URL(value);
+            return { valid: true, feedback: <div>Valid URL!</div> };
+        } catch (_) {
+            return { valid: false, feedback: <div>Invalid URL!</div>};
+        }
+    }
+
     onIdentityServerBlur = (ev) => {
         this._isTimeoutId = this._waitThenInvoke(this._isTimeoutId, () => {
             this.props.onServerConfigChange({
@@ -134,6 +143,7 @@ export default class ServerConfig extends React.PureComponent {
                         value={this.state.hsUrl}
                         onBlur={this.onHomeserverBlur}
                         onChange={this.onHomeserverChange}
+                        onValidate={this.onHomeserverValidate}
                     />
                     <Field id="mx_ServerConfig_isUrl"
                         label={_t("Identity Server URL")}
diff --git a/src/components/views/elements/ActionButton.js b/src/components/views/elements/ActionButton.js
index 1ca5ab9983..1eb082a917 100644
--- a/src/components/views/elements/ActionButton.js
+++ b/src/components/views/elements/ActionButton.js
@@ -69,8 +69,8 @@ export default React.createClass({
 
         let tooltip;
         if (this.state.showTooltip) {
-            const RoomTooltip = sdk.getComponent("rooms.RoomTooltip");
-            tooltip = <RoomTooltip className="mx_RoleButton_tooltip" label={this.props.label} />;
+            const Tooltip = sdk.getComponent("elements.Tooltip");
+            tooltip = <Tooltip className="mx_RoleButton_tooltip" label={this.props.label} />;
         }
 
         const icon = this.props.iconPath ?
diff --git a/src/components/views/elements/Field.js b/src/components/views/elements/Field.js
index c6a2113adb..eb3fcf272d 100644
--- a/src/components/views/elements/Field.js
+++ b/src/components/views/elements/Field.js
@@ -17,6 +17,7 @@ limitations under the License.
 import React from 'react';
 import PropTypes from 'prop-types';
 import classNames from 'classnames';
+import sdk from '../../../index';
 
 export default class Field extends React.PureComponent {
     static propTypes = {
@@ -33,9 +34,22 @@ export default class Field extends React.PureComponent {
         placeholder: PropTypes.string,
         // Optional component to include inside the field before the input.
         prefix: PropTypes.node,
+        // The callback called whenever the contents of the field
+        // changes.  Returns an object with `valid` boolean field
+        // and a `feedback` react component field to provide feedback
+        // to the user.
+        onValidate: PropTypes.function,
         // All other props pass through to the <input>.
     };
 
+    constructor() {
+        super();
+        this.state = {
+            valid: undefined,
+            feedback: undefined,
+        };
+    }
+
     get value() {
         if (!this.refs.fieldInput) return null;
         return this.refs.fieldInput.value;
@@ -48,8 +62,18 @@ export default class Field extends React.PureComponent {
         this.refs.fieldInput.value = newValue;
     }
 
+    onChange = (ev) => {
+        if (this.props.onValidate) {
+            const result = this.props.onValidate(this.value);
+            this.setState({
+                valid: result.valid,
+                feedback: result.feedback,
+            });
+        }
+    };
+
     render() {
-        const { element, prefix, children, ...inputProps } = this.props;
+        const { element, prefix, onValidate, children, ...inputProps } = this.props;
 
         const inputElement = element || "input";
 
@@ -58,6 +82,12 @@ export default class Field extends React.PureComponent {
         inputProps.ref = "fieldInput";
         inputProps.placeholder = inputProps.placeholder || inputProps.label;
 
+        inputProps.onChange = this.onChange;
+        // make sure we use the current `value` for the field and not the original one
+        if (this.value != undefined) {
+            inputProps.value = this.value;
+        }
+
         const fieldInput = React.createElement(inputElement, inputProps, children);
 
         let prefixContainer = null;
@@ -65,17 +95,34 @@ export default class Field extends React.PureComponent {
             prefixContainer = <span className="mx_Field_prefix">{prefix}</span>;
         }
 
-        const classes = classNames("mx_Field", `mx_Field_${inputElement}`, {
+        const validClass = classNames({
+            mx_Field_valid: this.state.valid === true,
+            mx_Field_invalid: this.state.valid === false,
+        });
+
+        const fieldClasses = classNames("mx_Field", `mx_Field_${inputElement}`, {
             // If we have a prefix element, leave the label always at the top left and
             // don't animate it, as it looks a bit clunky and would add complexity to do
             // properly.
             mx_Field_labelAlwaysTopLeft: prefix,
+            [validClass]: true,
         });
 
-        return <div className={classes}>
+        // handle displaying feedback on validity
+        const Tooltip = sdk.getComponent("elements.Tooltip");
+        let feedback;
+        if (this.state.feedback) {
+            feedback = <Tooltip
+                tooltipClassName={`mx_Field_tooltip ${validClass}`}
+                label={this.state.feedback}
+            />;
+        }
+
+        return <div className={fieldClasses}>
             {prefixContainer}
             {fieldInput}
             <label htmlFor={this.props.id}>{this.props.label}</label>
+            {feedback}
         </div>;
     }
 }
diff --git a/src/components/views/elements/TagTile.js b/src/components/views/elements/TagTile.js
index f5ee60a2d8..ef9864358b 100644
--- a/src/components/views/elements/TagTile.js
+++ b/src/components/views/elements/TagTile.js
@@ -156,7 +156,7 @@ export default React.createClass({
     render: function() {
         const BaseAvatar = sdk.getComponent('avatars.BaseAvatar');
         const AccessibleButton = sdk.getComponent('elements.AccessibleButton');
-        const RoomTooltip = sdk.getComponent('rooms.RoomTooltip');
+        const Tooltip = sdk.getComponent('elements.Tooltip');
         const profile = this.state.profile || {};
         const name = profile.name || this.props.tag;
         const avatarHeight = 40;
@@ -181,7 +181,7 @@ export default React.createClass({
         }
 
         const tip = this.state.hover ?
-            <RoomTooltip className="mx_TagTile_tooltip" label={name} /> :
+            <Tooltip className="mx_TagTile_tooltip" label={name} /> :
             <div />;
         const contextButton = this.state.hover || this.state.menuDisplayed ?
             <div className="mx_TagTile_context_button" onClick={this.onContextButtonClick}>
diff --git a/src/components/views/elements/ToolTipButton.js b/src/components/views/elements/ToolTipButton.js
index b5b2d735ee..239095f196 100644
--- a/src/components/views/elements/ToolTipButton.js
+++ b/src/components/views/elements/ToolTipButton.js
@@ -39,8 +39,8 @@ module.exports = React.createClass({
     },
 
     render: function() {
-        const RoomTooltip = sdk.getComponent("rooms.RoomTooltip");
-        const tip = this.state.hover ? <RoomTooltip
+        const Tooltip = sdk.getComponent("elements.Tooltip");
+        const tip = this.state.hover ? <Tooltip
             className="mx_ToolTipButton_container"
             tooltipClassName="mx_ToolTipButton_helpText"
             label={this.props.helpText}
diff --git a/src/components/views/rooms/RoomTooltip.js b/src/components/views/elements/Tooltip.js
similarity index 89%
rename from src/components/views/rooms/RoomTooltip.js
rename to src/components/views/elements/Tooltip.js
index bce0922637..473aeb3bdc 100644
--- a/src/components/views/rooms/RoomTooltip.js
+++ b/src/components/views/elements/Tooltip.js
@@ -1,5 +1,6 @@
 /*
 Copyright 2015, 2016 OpenMarket Ltd
+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.
@@ -23,22 +24,21 @@ import classNames from 'classnames';
 const MIN_TOOLTIP_HEIGHT = 25;
 
 module.exports = React.createClass({
-    displayName: 'RoomTooltip',
+    displayName: 'Tooltip',
 
     propTypes: {
         // Class applied to the element used to position the tooltip
-        className: React.PropTypes.string.isRequired,
+        className: React.PropTypes.string,
         // Class applied to the tooltip itself
         tooltipClassName: React.PropTypes.string,
-        // The tooltip is derived from either the room name or a label
-        room: React.PropTypes.object,
+        // the react element to put into the tooltip
         label: React.PropTypes.node,
     },
 
     // Create a wrapper for the tooltip outside the parent and attach it to the body element
     componentDidMount: function() {
         this.tooltipContainer = document.createElement("div");
-        this.tooltipContainer.className = "mx_RoomTileTooltip_wrapper";
+        this.tooltipContainer.className = "mx_Tooltip_wrapper";
         document.body.appendChild(this.tooltipContainer);
         window.addEventListener('scroll', this._renderTooltip, true);
 
@@ -85,11 +85,11 @@ module.exports = React.createClass({
         style = this._updatePosition(style);
         style.display = "block";
 
-        const tooltipClasses = classNames("mx_RoomTooltip", this.props.tooltipClassName);
+        const tooltipClasses = classNames("mx_Tooltip", this.props.tooltipClassName);
 
         const tooltip = (
             <div className={tooltipClasses} style={style}>
-                <div className="mx_RoomTooltip_chevron" />
+                <div className="mx_Tooltip_chevron" />
                 { this.props.label }
             </div>
         );
diff --git a/src/components/views/groups/GroupInviteTile.js b/src/components/views/groups/GroupInviteTile.js
index 44441f4754..8482bce593 100644
--- a/src/components/views/groups/GroupInviteTile.js
+++ b/src/components/views/groups/GroupInviteTile.js
@@ -143,8 +143,8 @@ export default React.createClass({
 
         let tooltip;
         if (this.props.collapsed && this.state.hover) {
-            const RoomTooltip = sdk.getComponent("rooms.RoomTooltip");
-            tooltip = <RoomTooltip className="mx_RoomTile_tooltip" label={groupName} dir="auto" />;
+            const Tooltip = sdk.getComponent("elements.Tooltip");
+            tooltip = <Tooltip className="mx_RoomTile_tooltip" label={groupName} dir="auto" />;
         }
 
         const classes = classNames('mx_RoomTile mx_RoomTile_highlight', {
diff --git a/src/components/views/messages/MStickerBody.js b/src/components/views/messages/MStickerBody.js
index 55263ef7b7..6a4128dfa7 100644
--- a/src/components/views/messages/MStickerBody.js
+++ b/src/components/views/messages/MStickerBody.js
@@ -44,9 +44,9 @@ export default class MStickerBody extends MImageBody {
 
         if (!content || !content.body || !content.info || !content.info.w) return null;
 
-        const RoomTooltip = sdk.getComponent('rooms.RoomTooltip');
+        const Tooltip = sdk.getComponent('elements.Tooltip');
         return <div style={{left: content.info.w + 'px'}} className="mx_MStickerBody_tooltip">
-            <RoomTooltip label={content.body} />
+            <Tooltip label={content.body} />
         </div>;
     }
 
diff --git a/src/components/views/rooms/RoomTile.js b/src/components/views/rooms/RoomTile.js
index f9e9d64b9e..4bf160007e 100644
--- a/src/components/views/rooms/RoomTile.js
+++ b/src/components/views/rooms/RoomTile.js
@@ -364,8 +364,8 @@ module.exports = React.createClass({
                 label = <EmojiText element="div" title={name} className={nameClasses} dir="auto">{ name }</EmojiText>;
             }
         } else if (this.state.hover) {
-            const RoomTooltip = sdk.getComponent("rooms.RoomTooltip");
-            tooltip = <RoomTooltip className="mx_RoomTile_tooltip" label={this.props.room.name} dir="auto" />;
+            const Tooltip = sdk.getComponent("elements.Tooltip");
+            tooltip = <Tooltip className="mx_RoomTile_tooltip" label={this.props.room.name} dir="auto" />;
         }
 
         //var incomingCallBox;