Thanks for raising this issue @Tom Robert. I found another similar issue http...

Thanks for raising this issue @Tom Robert. I found another similar issue https://www.drupal.org/project/redirect/issues/2991423 in the redirect module and as per it we can set

$disqus['language'] = \Drupal::languageManager()->getCurrentLanguage()->getId();

to

$disqus['language'] = \Drupal::languageManager()->getCurrentLanguage(LanguageInterface::TYPE_URL)->getId();

This can be a temporary solution till the time the core issue https://www.drupal.org/project/drupal/issues/3067007 is fixed or suggests anything.

@DamienMcKenna Do you have any suggestion on what should we do here?