### Please describe the problem.

The borg special remote is awesome and works perfectly if the borg repo is local. However, fetching content (e.g., with `git annex get` or `git annex sync --content`) seems to fail if the borg repo is accessed over ssh.

### What steps will reproduce the problem?

On remote host:

[[!format sh """
# Init borg repo
borg init --encryption=none /home/remote_user/borg_repo
"""]]

On local host:

[[!format sh """
# Set environment variable for clarity
export BORG_REPO=remote_user@remote_host:/home/remote_user/borg_repo

# Init git-annex repo on local host and add borg repo as semitrusted remote
git init git_repo && cd git_repo
git annex init git_repo
git annex initremote borg type=borg borgrepo=$BORG_REPO appendonly=yes

# Commit content to git-annex, create borg archive, and sync
echo content > file.txt
git annex add file.txt
git commit -m init
borg create $BORG_REPO::archive_name .
git annex sync borg

# Drop content from git-annex
git annex drop file.txt

# NOTE: Up to this point, everything is fine.

# Now, attempt to retrieve content from borg
git annex get file.txt
"""]]

The final step results in error. Please see the output below in the additional information section.

### What version of git-annex are you using? On what operating system?

- git-annex version: 8.20210428
- operation system: linux x86_64 (NixOS 21.05)

(NOTE: This was also tested on an old macOS machine with the same results.)

### Please provide any additional information below.

The following output shows an apparent concatenation of the local git-annex repo path with the remote borg repo path:

[[!format sh """
$ git annex get file.txt
get file.txt (from borg...)
Repository /home/local_user/git_repo/remote_user@remote_host:/home/remote_user/borg_repo does not exist.

  user error (borg ["extract","/home/local_user/git_repo/remote_user@remote_host:/home/remote_user/borg_repo::archive_name",".git/annex/objects/QV/p6/SHA256E-s8--12a61f4e173fb3a11c05d6471f74728f76231b4a5fcd9667cef3af87a3ae4dc3.txt/SHA256E-s8--12a61f4e173fb3a11c05d6471f74728f76231b4a5fcd9667cef3af87a3ae4dc3.txt"] exited 2)

  Unable to access these remotes: borg

  No other repository is known to contain the file.
failed
get: 1 failed
exit 1
"""]]

NOTE: I tried several variations of the ssh url syntax, but they all resulted in the same error.

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Definitely. I love git-annex. I LOVE it. It has no equal and is the secret to my productivity, not to mention peace of mind in this epoch. Much, much respect.

> [[fixed|done]] --[[Joey]]
