6 files declare their use of ActivityEntityConditionBase in Open Social 8.9

CommentAllActivityEntityCondition.php in modules/custom/activity_basics/src/Plugin/ActivityEntityCondition/CommentAllActivityEntityCondition.php

CommentNotReplyActivityEntityCondition.php in modules/custom/activity_basics/src/Plugin/ActivityEntityCondition/CommentNotReplyActivityEntityCondition.php

CommentReplyActivityEntityCondition.php in modules/custom/activity_basics/src/Plugin/ActivityEntityCondition/CommentReplyActivityEntityCondition.php

MentionCommentActivityEntityCondition.php in modules/social_features/social_mentions/src/Plugin/ActivityEntityCondition/MentionCommentActivityEntityCondition.php

MentionPostActivityEntityCondition.php in modules/social_features/social_mentions/src/Plugin/ActivityEntityCondition/MentionPostActivityEntityCondition.php

QueueStorageEntitySendActivityCondition.php in modules/custom/social_queue_storage/src/Plugin/ActivityEntityCondition/QueueStorageEntitySendActivityCondition.php