old_contents: from django.apps import AppConfig
  from django.core.checks import Tags, Warning, register
  from django.db import connection
  from django.utils.translation import gettext_lazy as _
  
  from wagtail.search.signal_handlers import register_signal_handlers
  
  
  class WagtailSearchAppConfig(AppConfig):
      name = 'wagtail.search'
      label = 'wagtailsearch'
      verbose_name = _("Wagtail search")
      default_auto_field = 'django.db.models.AutoField'
  
      def ready(self):
          register_signal_handlers()
  
          if connection.vendor == 'postgresql':
              # Only PostgreSQL has support for tsvector weights
              from wagtail.search.backends.database.postgres.weights import set_weights
              set_weights()
  
          from wagtail.search.models import IndexEntry
          IndexEntry.add_generic_relations()
  
      @register(Tags.compatibility, Tags.database)
      def check_if_sqlite_version_is_supported(app_configs, **kwargs):
          if connection.vendor == 'sqlite':
              import sqlite3
              if sqlite3.sqlite_version_info < (3, 19, 0):
                  return [Warning('Your SQLite version is older than 3.19.0. A fallback search backend will be used instead.', hint='Upgrade your SQLite version to at least 3.19.0', id='wagtailsearch.W002', obj=WagtailSearchAppConfig)]
          return []
  
new_contents: from django.apps import AppConfig
  from django.core.checks import Tags, Warning, register
  from django.db import connection
  from django.utils.translation import gettext_lazy as _
  
  from wagtail.search.signal_handlers import register_signal_handlers
  
  
  class WagtailSearchAppConfig(AppConfig):
      name = 'wagtail.search'
      label = 'wagtailsearch'
      verbose_name = _("Wagtail search")
      default_auto_field = 'django.db.models.AutoField'
  
      def ready(self):
          register_signal_handlers()
  
          if connection.vendor == 'postgresql':
              # Only PostgreSQL has support for tsvector weights
              from wagtail.search.backends.database.postgres.weights import set_weights
              set_weights()
  
          from wagtail.search.models import IndexEntry
          IndexEntry.add_generic_relations()
  
      @register(Tags.compatibility, Tags.database)
      def check_if_sqlite_version_is_supported(app_configs, **kwargs):
          if connection.vendor == 'sqlite':
              import sqlite3
  
              from wagtail.search.backends.database.sqlite.utils import fts5_available
  
              if sqlite3.sqlite_version_info < (3, 19, 0):
                  return [Warning('Your SQLite version is older than 3.19.0. A fallback search backend will be used instead.', hint='Upgrade your SQLite version to at least 3.19.0', id='wagtailsearch.W002', obj=WagtailSearchAppConfig)]
              elif not fts5_available():
                  return [Warning('Your SQLite installation is missing the fts5 extension. A fallback search backend will be used instead.', hint='Upgrade your SQLite installation to a version with fts5 enabled', id='wagtailsearch.W003', obj=WagtailSearchAppConfig)]
          return []
  
subject: Add alternative warning if sqlite is >=3.19 but is missing fts5 support