discourse/plugins/chat/assets/stylesheets/desktop/chat-message-thread-indicator.scss

.chat-message-thread-indicator {
  width: min-content;
  min-width: 400px;
  max-width: 600px;

  .chat-drawer & {
    align-items: stretch;
    flex-wrap: wrap;
    width: auto;
    max-width: 100%;
    min-width: auto;
    gap: 0.25rem;
  }

  &__last-reply-avatar {
    .chat-drawer & {
      display: inline-block;
    }
  }

  &__last-reply-user {
    margin-right: 0.25rem;

    .chat-drawer & {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      margin-right: auto;
    }
  }

  &__last-reply-metadata {
    .chat-drawer & {
      flex-wrap: wrap;
    }
  }

  &__last-reply-excerpt {
    .chat-drawer & {
      white-space: wrap;
      display: -webkit-box;
      -webkit-line-clamp: 3;
      -webkit-box-orient: vertical;
      margin-left: calc(26px + 0.5rem);
    }
  }

  &__body {
    .chat-drawer & {
      flex-grow: 1;
    }
  }
  &__participants {
    margin-left: auto;

    .chat-drawer & {
      align-self: flex-end;
      flex-basis: 100%;
    }
  }
}