External storage $user contains characters not valid for S3 bucket names


I’m using nextcloud 20.0.1 with external storage locations on S3.

I’d like to add further S3 storage locations from another S3 provider. However, the new provider does not allow the ‘.’ character in bucket names, and unfortunately many of my user names have a ‘.’ in them. This also applies to the ‘@’ character, which might also be quite common in user names.

It seems that there are differences in naming schemes for buckets, but fact is there are S3 providers with strict limitations which might conflict with $user:

Is there a way to replace characters in $user in the configuration of external storag locations?

kind regards,