7 files declare their use of Menu in Zircon Profile 8

block.module in core/modules/block/block.module

Controls the visual building blocks a page is constructed with.

BlockXssTest.php in core/modules/block/src/Tests/BlockXssTest.php

Contains \Drupal\block\Tests\BlockXssTest.

MenuLinkContentDeleteFormTest.php in core/modules/menu_link_content/src/Tests/MenuLinkContentDeleteFormTest.php

Contains \Drupal\menu_link_content\Tests\MenuLinkContentDeleteFormTest.

MenuTest.php in core/modules/menu_ui/src/Tests/MenuTest.php

Contains \Drupal\menu_ui\Tests\MenuTest.

MenuUninstallTest.php in core/modules/menu_ui/src/Tests/MenuUninstallTest.php

Contains \Drupal\menu_ui\Tests\MenuUninstallTest.

menu_ui.module in core/modules/menu_ui/menu_ui.module

Allows administrators to customize the site's navigation menus.

MigrateMenuTest.php in core/modules/system/src/Tests/Migrate/MigrateMenuTest.php

Contains \Drupal\system\Tests\Migrate\MigrateMenuTest.