Related posts when using internal tags

Hi,

I currently have a “Related articles” section on my blog where I display related articles based on their tags, but I notice that after using internal tags for internationalization (#fr or #en by example), my related articles are no so related anymore.

{{~#get "posts"
       limit="4"
       filter="tags:[{{post.tags}}]+id:-{{post.id}}"
       include="tags" as |post_related|
~}}

As post.tags includes internal tags like #en, the get request is equivalent to requesting all posts written in English… :see_no_evil:

A partial solution that I’ve found is to use primary_tag instead, but it’s not 100% equivalent, as it only gives me posts with the same primary tag…

Does anyone know how I could exclude internal tags from my get request?

Thank you!

Ben