discourse/app/assets/javascripts/admin/templates/components/themes-list.hbs

<div class="themes-list-header">
  <div {{action "changeView" THEMES}} class="themes-tab tab {{if themesTabActive 'active' ''}}">
    {{d-icon "cube"}}
    {{I18n "admin.customize.theme.title"}}
  </div><div {{action "changeView" COMPONENTS}} class="components-tab tab {{if componentsTabActive 'active' ''}}">
    {{I18n "admin.customize.theme.components"}}
  </div>
</div>

<div class="themes-list-container">
  {{#if hasThemes}}
    {{#if componentsTabActive}}
      {{#each themesList as |theme|}}
        {{themes-list-item theme=theme navigateToTheme=(action "navigateToTheme" theme)}}
      {{/each}}
    {{else}}
      {{#if hasUserThemes}}
        {{#each userThemes as |theme|}}
          {{themes-list-item theme=theme navigateToTheme=(action "navigateToTheme" theme)}}
        {{/each}}

        {{#if hasInactiveThemes}}
          <div class="themes-list-item inactive-indicator">
            <span class="empty">{{I18n "admin.customize.theme.inactive_themes"}}</span>
          </div>
        {{/if}}
      {{/if}}

      {{#if hasInactiveThemes}}
        {{#each inactiveThemes as |theme|}}
          {{themes-list-item theme=theme navigateToTheme=(action "navigateToTheme" theme)}}
        {{/each}}
      {{/if}}
    {{/if}}
  {{else}}
    <div class="themes-list-item">
      <span class="empty">{{I18n "admin.customize.theme.empty"}}</span>
    </div>
  {{/if}}
</div>