public BlockBase::getMachineNameSuggestion() Suggests

The theme handler. Type:

public Block::postSave(EntityStorageInterface $storage, $update = TRUE)

Indicates the block label (title) should be displayed to end users. File core/modules/block/src/BlockInterface

block_install() Implements

block_user_role_delete($role) Implements

public BlockInterface::getVisibilityConditions()