### Please describe the problem.

I have set up a host machine and a VM with git annex assistant 'Local computer' sharing. When pairing the pairing gets stuck at 'Pairing in progress ..' and I have to manually click on 
dashbord desite sync succeeding.
When I modify and safe one file on the host the transfer bar gets almost always stuck
at 100% and the respective file on the VM only shows the SHA instead of the actual content, or after some stuck transfer files simply don't get updated anymore. (Same behaviour when transferring vice versa)
I then have to cancel the transfer and run git annex get on the VM, defeating the purpose of the annex assistant.


### What steps will reproduce the problem?

- Setup file sharing via git annex assistant 'Local computer' sharing (behaviour probably also via remote server)
- Notice that pairing gets stuck at 'Pairing in progress..' but sync succeeds.
- Click on Dashbord
- Create files in the shared folder
- Modify files alternately on both machines until status bar gets stuck at 100% for many files (around 90%-100% of times)
- Notice that respective file on other machine contains only SHA instead of updated content or does not get updated anymore.

### What version of git-annex are you using? On what operating system?
8.20200330-7 on manjaro-kde-19.0.2-200311-linux54

### Please provide any additional information below.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log
[2020-04-15 13:48:21.7056893] main: starting assistant version 8.20200330-gdbad6c5c3
[2020-04-15 13:48:21.718362084] Cronner: You should enable consistency checking to protect your data. 
(scanning...) [2020-04-15 13:48:21.912322575] Watcher: Performing startup scan
(started...) 
Generating public/private rsa key pair.
Your identification has been saved in /tmp/git-annex-keygenI1lLqc/key
Your public key has been saved in /tmp/git-annex-keygenI1lLqc/key.pub
The key fingerprint is:
SHA256:5V7j4+jy3W/D7hT+rBExiTQcB+WDwBoIkkplPIEKbqQ alejandra@alejandra-pc
The key's randomart image is:
+---[RSA 3072]----+
|  ==o. . ...=+o  |
|.+o+  . . .o.* . |
|B.  .    o. o *  |
|Eo      .o     + |
|.       S . o .. |
|         . o ....|
|          . o oo |
|        .  + o.=o|
|         ++ o =*=|
+----[SHA256]-----+
[2020-04-15 13:48:38.095033553] main: Pairing in progress
Generating public/private rsa key pair.
Your identification has been saved in /tmp/git-annex-keygenoF74Qa/key
Your public key has been saved in /tmp/git-annex-keygenoF74Qa/key.pub
The key fingerprint is:
SHA256:lVu+FAF9gP/jGOamjGbFzXFx1uT4Hfy0GIdoDbZLwcU alejandra@alejandra-pc
The key's randomart image is:
+---[RSA 3072]----+
|          oB=o .o|
|          ooBE=o+|
|          o*o=.Bo|
|         .o++.=o=|
|        S..+o= .+|
|          o.=.o  |
|         . o.+ . |
|        oo  + .  |
|       o. oo     |
+----[SHA256]-----+
[2020-04-15 13:49:57.556502118] main: Pairing in progress
[2020-04-15 13:50:30.588506645] PairListener: Syncing with manjarobios.local_Desktop_annex 
warning: no common commits
From ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex
 * [new branch]      adjusted/master(unlocked) -> manjarobios.local_Desktop_annex/adjusted/master(unlocked)
 * [new branch]      git-annex  -> manjarobios.local_Desktop_annex/git-annex
 * [new branch]      master     -> manjarobios.local_Desktop_annex/master
(merging manjarobios.local_Desktop_annex/git-annex into git-annex...)
(recording state in git...)
(Merging into master...) Already up to date!
Merge made by the 'recursive' strategy.
(Merging into adjusted branch...) 
Updating 4c91e84..6342378
Fast-forward
[2020-04-15 13:50:33.654970467] Pusher: Syncing with manjarobios.local_Desktop_annex 
remote: error: cannot lock ref 'refs/heads/synced/git-annex': reference already exists        
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
 ! [remote rejected] git-annex -> synced/git-annex (failed to update ref)
error: failed to push some refs to 'ssh://manjarobios@git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/'
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   136b79c..305df7c  master -> synced/master
 * [new branch]      git-annex -> synced/git-annex
From ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex
 + 0872b3a...ed5e6fb adjusted/master(unlocked) -> manjarobios.local_Desktop_annex/adjusted/master(unlocked)  (forced update)
Everything up-to-date
[2020-04-15 13:54:38.785014695] Committer: Adding TestFile1.txt
add TestFile1.txt ok
[2020-04-15 13:54:38.846796771] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:54:38.908886364] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)


100%  2 B                 1 B/s 0s
                                  
[2020-04-15 13:54:41.563838822] Transferrer: Uploaded TestFile1.txt
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   351d3ca..c1900de  git-annex -> synced/git-annex
   305df7c..5b93460  master -> synced/master
[2020-04-15 13:54:47.631284311] Committer: Adding TestFile1.txt
add TestFile1.txt ok
[2020-04-15 13:54:47.656086205] Committer: Committing changes to git
(recording state in git...)


100%  17 B              986 B/s 0s
                                  
[2020-04-15 13:54:47.859686766] Transferrer: Uploaded TestFile1.txt
[2020-04-15 13:54:47.93982864] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)
(merging synced/git-annex into git-annex...)
(recording state in git...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   c1900de..46b5173  git-annex -> synced/git-annex
   5b93460..c3dbb6f  master -> synced/master
(merging synced/git-annex into git-annex...)
(merging synced/git-annex into git-annex...)
(Merging into master...) Updating c3dbb6f..3cb38cd
Fast-forward
 TestFile1.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
(Merging into adjusted branch...) 
Updating e2cde79..640c290
Fast-forward
 TestFile1.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2020-04-15 13:56:23.138926931] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:56:23.230412042] Pusher: Syncing with manjarobios.local_Desktop_annex 


100%  32 B              182 B/s 0s
                                  
(checksum...) [2020-04-15 13:56:23.471654381] Transferrer: Downloaded TestFile1.txt
[2020-04-15 13:56:24.67751826] Committer: Adding TestFile1.txt
add TestFile1.txt ok
[2020-04-15 13:56:24.692071343] Committer: Committing changes to git
(recording state in git...)
(merging synced/git-annex into git-annex...)
(recording state in git...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   46b5173..bc7da3b  git-annex -> synced/git-annex
[2020-04-15 13:56:37.508510449] Pusher: Syncing with manjarobios.local_Desktop_annex 
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   bc7da3b..9d994e6  git-annex -> synced/git-annex
(merging synced/git-annex into git-annex...)
(recording state in git...)
(Merging into master...) Updating 3cb38cd..644b2c2
Fast-forward
 TestFile1.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
(Merging into adjusted branch...) 
Updating 2efdbac..3ad6997
Fast-forward
 TestFile1.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2020-04-15 13:57:26.572140658] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:57:26.711267728] Pusher: Syncing with manjarobios.local_Desktop_annex 
[2020-04-15 13:57:28.045186493] Committer: Adding TestFile1.txt
add TestFile1.txt ok
[2020-04-15 13:57:28.067821299] Committer: Committing changes to git
(recording state in git...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   9d994e6..ac253ff  git-annex -> synced/git-annex
   644b2c2..c0ef509  master -> synced/master
[2020-04-15 13:57:37.205281607] Committer: Adding TestFile1.txt
(merging synced/git-annex into git-annex...)
(recording state in git...)
add TestFile1.txt ok
[2020-04-15 13:57:37.344736169] Committer: Committing changes to git
(recording state in git...)


100%  63 B              3 KiB/s 0s
                                  
[2020-04-15 13:57:37.604509822] Transferrer: Uploaded TestFile1.txt
[2020-04-15 13:57:43.872997704] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   ac253ff..301cec6  git-annex -> synced/git-annex
   ffebc7f..71d50f9  master -> synced/master
(merging synced/git-annex into git-annex...)
(Merging into master...) Updating 71d50f9..d6fbcef
Fast-forward
 TextFileCreadedByVm.txt | 1 +
 1 file changed, 1 insertion(+)
 create mode 120000 TextFileCreadedByVm.txt
(Merging into adjusted branch...) 
Updating 6cf6158..e464f35
Fast-forward
 TextFileCreadedByVm.txt | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 TextFileCreadedByVm.txt
[2020-04-15 13:58:28.922447217] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:58:29.003532092] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)
[2020-04-15 13:58:30.121232466] Committer: Committing changes to git
(recording state in git...)
(merging synced/git-annex into git-annex...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   301cec6..8a60331  git-annex -> synced/git-annex
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'ssh://manjarobios@git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
(merging synced/git-annex into git-annex...)
(recording state in git...)
(Merging into master...) Updating d6fbcef..3f389fd
Fast-forward
 TextFileCreadedByVm.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2020-04-15 13:58:43.352572624] Pusher: Syncing with manjarobios.local_Desktop_annex 
(Merging into adjusted branch...) 
Updating 6f7e537..411e021
Fast-forward
 TextFileCreadedByVm.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2020-04-15 13:58:46.473084994] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:58:47.879634494] Committer: Adding TextFileC..dByVm.txt
add TextFileCreadedByVm.txt ok
[2020-04-15 13:58:47.90195794] Committer: Committing changes to git
(recording state in git...)
(merging synced/git-annex into git-annex...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   8a60331..fb78a8e  git-annex -> synced/git-annex
[2020-04-15 13:59:01.63874079] Pusher: Syncing with manjarobios.local_Desktop_annex 
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   fb78a8e..e44b5a7  git-annex -> synced/git-annex
[2020-04-15 13:59:16.580076548] Committer: Adding TextFileC..dByVm.txt
add TextFileCreadedByVm.txt ok
[2020-04-15 13:59:16.602073897] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:59:16.657771598] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)


100%  33 B              3 KiB/s 0s
                                  
[2020-04-15 13:59:16.768196257] Transferrer: Uploaded TextFileC..dByVm.txt
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   e44b5a7..b2ab43f  git-annex -> synced/git-annex
   0e228b8..16959d0  master -> synced/master
[2020-04-15 13:59:28.352892434] Pusher: Syncing with manjarobios.local_Desktop_annex 
(recording state in git...)
(merging synced/git-annex into git-annex...)
(recording state in git...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   b2ab43f..1cddb88  git-annex -> synced/git-annex
(merging synced/git-annex into git-annex...)
(recording state in git...)
(Merging into master...) Updating 16959d0..42aeae0
Fast-forward
 TextFileCreadedByVm.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
(Merging into adjusted branch...) 
Updating cc589d4..8108c64
Fast-forward
 TextFileCreadedByVm.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
[2020-04-15 13:59:49.422226799] Committer: Adding TextFileC..dByVm.txt
add TextFileCreadedByVm.txt ok
[2020-04-15 13:59:49.43447346] Committer: Committing changes to git
(recording state in git...)
[2020-04-15 13:59:49.47331159] Pusher: Syncing with manjarobios.local_Desktop_annex 
(merging synced/git-annex into git-annex...)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
   1cddb88..f85dba3  git-annex -> synced/git-annex
fd:72: hPutStr: illegal operation (handle is closed)
(Merging into master...) Updating 42aeae0..88cba5b
Fast-forward
 TextFileCreadedByVm.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
To ssh://git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'ssh://manjarobios@git-annex-manjarobios.local-manjarobios_22_Desktop.2Fannex/~/Desktop/annex/'
hint: Updates were rejected because a pushed branch tip is behind its remote
hint: counterpart. Check out this branch and integrate the remote changes
hint: (e.g. 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
fd:72: hPutStr: illegal operation (handle is closed)
[2020-04-15 14:00:59.469617044] Committer: Adding TextFileC..dByVm.txt
add TextFileCreadedByVm.txt (Merging into master...) Updating 88cba5b..b1c4ef8
Fast-forward
 TextFromVm2.txt | 1 +
 1 file changed, 1 insertion(+)
 create mode 120000 TextFromVm2.txt
[2020-04-15 14:02:43.220016515] Committer: Adding TextFileC..dByVm.txt
add TextFileCreadedByVm.txt 

# End of transcript or log.
"""]]

### 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)


