6 files declare their use of SectionStorage

DefaultsSectionStorage.php in core/modules/layout_builder/src/Plugin/SectionStorage/DefaultsSectionStorage.php
NavigationSectionStorage.php in core/modules/navigation/src/Plugin/SectionStorage/NavigationSectionStorage.php
OverridesSectionStorage.php in core/modules/layout_builder/src/Plugin/SectionStorage/OverridesSectionStorage.php
SectionStorageManager.php in core/modules/layout_builder/src/SectionStorage/SectionStorageManager.php
SimpleConfigSectionStorage.php in core/modules/layout_builder/tests/modules/layout_builder_test/src/Plugin/SectionStorage/SimpleConfigSectionStorage.php
TestStateBasedSectionStorage.php in core/modules/layout_builder/tests/modules/layout_builder_test/src/Plugin/SectionStorage/TestStateBasedSectionStorage.php

Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.