old_contents: from django.contrib import admin
  from article.models import Article, ArticleTextItem
  from fluent_contents.admin import PlaceholderFieldAdmin
  
  
  class ArticleAdmin(PlaceholderFieldAdmin):
      prepopulated_fields = {'slug': ('title',)}
  
      fieldsets = (
          (None, {
              'fields': ('title', 'slug'),
          }),
          ("Contents", {
              'fields': ('content',),
              'classes': ('plugin-holder',),
          })
      )
  
  admin.site.register(Article, ArticleAdmin)
  
  
  
  # For debugging:
  
  class ArticleTextItemAdmin(admin.ModelAdmin):
      list_display = ('text', 'parent')
  
  admin.site.register(ArticleTextItem, ArticleTextItemAdmin)
  
new_contents: from django.contrib import admin
  from article.models import Article, ArticleTextItem
  from fluent_contents.admin import PlaceholderFieldAdmin
  
  
  class ArticleAdmin(PlaceholderFieldAdmin):
      prepopulated_fields = {'slug': ('title',)}
  
      fieldsets = (
          (None, {
              'fields': ('title', 'slug'),
          }),
          ("Contents", {
              'fields': ('content',),
              'classes': ('plugin-holder',),
          })
      )
  
  admin.site.register(Article, ArticleAdmin)
  
  
  
  # For debugging:
  
  #class ArticleTextItemAdmin(admin.ModelAdmin):
  #    list_display = ('text', 'parent')
  #
  #admin.site.register(ArticleTextItem, ArticleTextItemAdmin)
  
subject: hide Article text items