19 files declare their use of Config in Backup and Migrate 5.0.x

backup_migrate.module in ./backup_migrate.module

Primary hook implementations for Backup Migrate.

CompressionFilter.php in src/Core/Filter/CompressionFilter.php

DatabaseSource.php in src/Core/Source/DatabaseSource.php

DBExcludeFilter.php in src/Core/Filter/DBExcludeFilter.php

DebugDestination.php in src/Core/Destination/DebugDestination.php

DefaultDBSourcePlugin.php in src/Plugin/BackupMigrateSource/DefaultDBSourcePlugin.php

DrupalEncrypt.php in src/Drupal/Filter/DrupalEncrypt.php

DrupalFilesSourcePlugin.php in src/Plugin/BackupMigrateSource/DrupalFilesSourcePlugin.php

DrupalPublicFileExcludeFilter.php in src/Drupal/Filter/DrupalPublicFileExcludeFilter.php

DrupalPublicFilesSource.php in src/Drupal/Source/DrupalPublicFilesSource.php

DrupalUtils.php in src/Drupal/Filter/DrupalUtils.php

EntireSiteSourcePlugin.php in src/Plugin/BackupMigrateSource/EntireSiteSourcePlugin.php

FileDirectorySource.php in src/Core/Source/FileDirectorySource.php

FileExcludeFilter.php in src/Core/Filter/FileExcludeFilter.php

FileNamer.php in src/Core/Filter/FileNamer.php

MetadataWriter.php in src/Core/Filter/MetadataWriter.php

PluginManager.php in src/Core/Plugin/PluginManager.php

Schedule.php in src/Entity/Schedule.php

WrapperPluginBase.php in src/Drupal/EntityPlugins/WrapperPluginBase.php