Snapshot listing mixes repositories up

Hi all,
sorry if this has been answered already but I couldn't find answers around.
I have a cluster running 3 indices and for some automation, I registered a separated repository on S3 for each of them.
Each repository has the same name as the index for which it has been created (index1 in the repository index1 and so).

Writing some script that cleans things up, I need a listing of the snapshots for a given repository, this way:

curl -XGET 'localhost:9200/_snapshot/index1/_all?pretty'

But this returns the snapshots of all the repositories although each of them has a different name.

My questions:

  1. Is using a different repo for each index running on the same cluster a bad approach?
  2. is there something I am missing on how to list the snapshots for a given repository?
  3. have I just found a bug?
  4. Is it because they all are in the same S3 bucket?

Thanks in advance for your time!

I received an answer on github:

And it seems that using the same bucket for more repositories causes this behavior.