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#12 /var/www/html/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(142): call_user_func() #11 : Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray() #10 /var/www/html/core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php(90): Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse() #9 /var/www/html/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(132): Drupal\Core\Render\MainContent\HtmlRenderer->prepare() #8 /var/www/html/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(274): Drupal\block\Plugin\DisplayVariant\BlockPageVariant->build() #7 /var/www/html/core/modules/block/src/Plugin/DisplayVariant/BlockPageVariant.php(137): Drupal\block\BlockRepository->getVisibleBlocksPerRegion() #6 /var/www/html/core/modules/block/src/BlockRepository.php(56): Drupal\Core\Theme\ThemeManager->getActiveTheme()
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#5 /var/www/html/core/lib/Drupal/Core/Theme/ThemeManager.php(96): Drupal\Core\Theme\ThemeManager->initTheme() #4 /var/www/html/core/lib/Drupal/Core/Theme/ThemeManager.php(405): Drupal\Core\Theme\ThemeNegotiator->determineActiveTheme() #3 /var/www/html/core/lib/Drupal/Core/Theme/ThemeNegotiator.php(67): Drupal\styleguide\Theme\StyleguideThemeNegotiator->applies() #2 /var/www/html/modules/contrib/styleguide/src/Theme/StyleguideThemeNegotiator.php(60): strpos()
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#Php strpos upgrade#
After upgrade to PHP 8.1 debug log reported as below: Deprecated function: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated in Drupal\styleguide\Theme\StyleguideThemeNegotiator->applies() (line 60 of /var/www/html/modules/contrib/styleguide/src/Theme/StyleguideThemeNegotiator.php)
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