10 methods override ThemeNegotiatorInterface::determineActiveTheme()

AdminDemoNegotiator::determineActiveTheme in core/modules/block/src/Theme/AdminDemoNegotiator.php
AdminNegotiator::determineActiveTheme in core/modules/user/src/Theme/AdminNegotiator.php
AjaxBasePageNegotiator::determineActiveTheme in core/lib/Drupal/Core/Theme/AjaxBasePageNegotiator.php
BatchNegotiator::determineActiveTheme in core/modules/system/src/Theme/BatchNegotiator.php
CustomThemeNegotiator::determineActiveTheme in core/modules/system/tests/modules/theme_test/src/Theme/CustomThemeNegotiator.php
DbUpdateNegotiator::determineActiveTheme in core/modules/system/src/Theme/DbUpdateNegotiator.php
DefaultNegotiator::determineActiveTheme in core/lib/Drupal/Core/Theme/DefaultNegotiator.php
HighPriorityThemeNegotiator::determineActiveTheme in core/modules/system/tests/modules/theme_test/src/Theme/HighPriorityThemeNegotiator.php
TestThemeNegotiator::determineActiveTheme in core/modules/system/tests/modules/menu_test/src/Theme/TestThemeNegotiator.php
ThemeNegotiator::determineActiveTheme in core/lib/Drupal/Core/Theme/ThemeNegotiator.php

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