17 files declare their use of GroupBase in Metatag 8

AndroidMobile.php in metatag_mobile/src/Plugin/metatag/Group/AndroidMobile.php

AppleMobile.php in metatag_mobile/src/Plugin/metatag/Group/AppleMobile.php

AppLinks.php in metatag_app_links/src/Plugin/metatag/Group/AppLinks.php

DublinCore.php in metatag_dc/src/Plugin/metatag/Group/DublinCore.php

DublinCoreAdvanced.php in metatag_dc_advanced/src/Plugin/metatag/Group/DublinCoreAdvanced.php

Facebook.php in metatag_facebook/src/Plugin/metatag/Group/Facebook.php

Favicons.php in metatag_favicons/src/Plugin/metatag/Group/Favicons.php

GoogleCse.php in metatag_google_cse/src/Plugin/metatag/Group/GoogleCse.php

GooglePlus.php in metatag_google_plus/src/Plugin/metatag/Group/GooglePlus.php

Hreflang.php in metatag_hreflang/src/Plugin/metatag/Group/Hreflang.php

Mobile.php in metatag_mobile/src/Plugin/metatag/Group/Mobile.php

OpenGraph.php in metatag_open_graph/src/Plugin/metatag/Group/OpenGraph.php

OpenGraphProducts.php in metatag_open_graph_products/src/Plugin/metatag/Group/OpenGraphProducts.php

Pinterest.php in metatag_pinterest/src/Plugin/metatag/Group/Pinterest.php

SiteVerification.php in metatag_verification/src/Plugin/metatag/Group/SiteVerification.php

TwitterCards.php in metatag_twitter_cards/src/Plugin/metatag/Group/TwitterCards.php

WindowsMobile.php in metatag_mobile/src/Plugin/metatag/Group/WindowsMobile.php