Try a slightly larger HostingSignupDialog

Make HostingSignupBaseDialog larger

res/css/views/dialogs/_HostingSignupDialog.scss

@@ -15,7 +15,8 @@ limitations under the License.
 */
 
 .mx_HostingSignupDialog .mx_Dialog {
-    height: 50%;
+    height: 66%;
+    min-width: 50%;
 }
 
 .mx_HostingSignupBaseDialog {
@@ -23,7 +24,7 @@ limitations under the License.
 }
 
 .mx_HostingSignupDialog_container {
-    height: 95%;
+    height: 90%;
 
     iframe {
         width: 100%;

src/components/views/dialogs/HostingSignupDialog.tsx

@@ -138,6 +138,7 @@ export default class HostingSignupDialog extends React.PureComponent<IProps, ISt
                 onFinished={this.onFinished}
                 title="Set up your own personal Element host"
                 hasCancel={true}
+                fixedWidth={false}
             >
                 <div className="mx_HostingSignupDialog_container">
                     <iframe