19 files declare their use of SensorPluginBase in Monitoring 8

CoreRequirementsSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/CoreRequirementsSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\CoreRequirementsSensorPlugin.

CronLastRunAgeSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/CronLastRunAgeSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\CronLastRunAgeSensorPlugin.

DatabaseDiskUsagePlugin.php in src/Plugin/monitoring/SensorPlugin/DatabaseDiskUsagePlugin.php

DisappearedSensorsSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/DisappearedSensorsSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\DisappearedSensorsSensorPlugin.

DiskUsageSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/DiskUsageSensorPlugin.php

ElysiaCronSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/ElysiaCronSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\ElysiaCronSensorPlugin.

EnabledModulesSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/EnabledModulesSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\EnabledModulesSensorPlugin.

GitDirtyTreeSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/GitDirtyTreeSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\GitDirtyTreeSensorPlugin.

QueueSizeSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/QueueSizeSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\QueueSizeSensorPlugin.

SearchApiUnindexedSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/SearchApiUnindexedSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\SearchApiUnindexedSensorPlugin.

SolrDiskUsageSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/SolrDiskUsageSensorPlugin.php

SystemLoadSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/SystemLoadSensorPlugin.php

SystemMemorySensorPlugin.php in src/Plugin/monitoring/SensorPlugin/SystemMemorySensorPlugin.php

TestSensorPlugin.php in modules/test/src/Plugin/monitoring/SensorPlugin/TestSensorPlugin.php

Contains \Drupal\monitoring_test\Plugin\monitoring\SensorPlugin\TestSensorPlugin.

TwigDebugSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/TwigDebugSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\TwigDebugSensorPlugin.

UltimateCronErrorsSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/UltimateCronErrorsSensorPlugin.php

UpdateStatusSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/UpdateStatusSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\UpdateStatusSensorPlugin.

UserIntegritySensorPlugin.php in src/Plugin/monitoring/SensorPlugin/UserIntegritySensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\UserIntegritySensorPlugin.

ViewDisplayAggregatorSensorPlugin.php in src/Plugin/monitoring/SensorPlugin/ViewDisplayAggregatorSensorPlugin.php

Contains \Drupal\monitoring\Plugin\monitoring\SensorPlugin\ViewDisplayAggregatorSensorPlugin.