Usernames: Create/update/delete in profile editor

stylesheets/components/AvatarPreview.scss

@@ -33,6 +33,12 @@
       background-size: cover;
       background-position: center center;
     }
+
+    @include keyboard-mode {
+      &:focus {
+        box-shadow: 0 0 0 3px $color-ultramarine;
+      }
+    }
   }
 
   &__group {

stylesheets/components/ConversationDetails.scss

@@ -165,8 +165,12 @@
       padding: none;
 
       &:focus {
-        @include mouse-mode {
-          outline: none;
+        outline: none;
+
+        .ConversationDetails-icon__icon::after {
+          @include keyboard-mode {
+            background-color: $color-ultramarine;
+          }
         }
       }
     }

stylesheets/components/ProfileEditor.scss

@@ -35,6 +35,12 @@
       }
     }
 
+    &--username {
+      &::after {
+        -webkit-mask: url(../images/icons/v2/at-24.svg) no-repeat center;
+      }
+    }
+
     &--bio {
       &::after {
         -webkit-mask: url(../images/icons/v2/compose-outline-24.svg) no-repeat
@@ -71,6 +77,13 @@
     }
   }
 
+  &__error {
+    @include font-body-2;
+    margin: 16px 0;
+
+    color: $color-accent-red;
+  }
+
   &__info {
     @include font-body-2;
     margin: 16px 0;