deleteAccount => show warning when recover will generate new SessionID

stylesheets/_session.scss

@@ -565,6 +565,7 @@ label {
   &-wrapper {
     .session-modal__body .session-modal__centered {
       margin: $session-margin-lg;
+      text-align: center;
     }
   }
 

stylesheets/manifest.scss

@@ -4,9 +4,9 @@
 @import 'node_modules/react-contexify/dist/ReactContexify.min.css';
 @import 'node_modules/react-toastify/dist/ReactToastify.css';
 
-@import 'node_modules/sanitize.css/sanitize.css';
-@import 'node_modules/sanitize.css/forms.css';
-@import 'node_modules/sanitize.css/typography.css';
+// @import url(sanitize.css);
+// @import url(forms.css);
+// @import url(typography.css);
 
 // Global Settings, Variables, and Mixins
 @import 'themes.scss';

ts/components/session/LeftPaneSettingSection.tsx

@@ -178,7 +178,7 @@ export class LeftPaneSettingSection extends React.Component<Props, State> {
       isSecondaryDevice ? 'unpairDevice' : 'clearAllData'
     );
 
-    const message = window.i18n(
+    let message = window.i18n(
       isSecondaryDevice ? 'unpairDeviceWarning' : 'deleteAccountWarning'
     );
 
@@ -186,6 +186,11 @@ export class LeftPaneSettingSection extends React.Component<Props, State> {
       ? window.i18n('unpairDeviceWarningSub')
       : '';
 
+    const identityKey = window.textsecure.storage.get('identityKey');
+    if (identityKey && identityKey.ed25519KeyPair === undefined) {
+      message = `${message} We've updated the way Session IDs are generated, so you will not be able to restore your current Session ID.`;
+    }
+
     window.confirmationDialog({
       title,
       message,