How to stop WP from automatically update .po and .mo file translations

For my site a made own Dutch translation of a plugin. So I made a .po and .mo file.

But WP is constantly putting old versions of those in wp-content/languages/plugins

I tried a lot to stop this, but none of them work.

Amongst:

// Disable translation updates
if( function_exists(‘add_filter’) ) {
add_filter( ‘auto_update_translation’, ‘__return_false’ );
}

and

define( ‘WP_AUTO_UPDATE_TRANSLATION’, false ); (WP-config)

But more than ones a day I get new files in the wp-content/languages/plugins folder.

How to stop this? Preferably for a specific plugin, but when not possible than stop this completely.

Thanks,

Bert

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