JabRef 5.1--2020-06-30--5f2b994
on Linux 4.12.14-lp151.28.52-default amd64 (openSUSE Leap 15.1)
with Java 14.0.1

I have tested the latest development version from http://builds.jabref.org/master/ and the problem persists

When I use shared PostgreSQL database, user inputs are not synced properly. Only the first character is saved to database.

Steps to reproduce the behavior:

1. I have a shared PostgreSQL database with ~5600 entries.
2. Via GUI and keyboard, I type in entry field content (e.g. Note under Optional fields), for example '12345'.
3. Before displaying first input character, I have to wait ~7 seconds. Then, every input seems to be saved to database.
4. Reopening database reveals that only the first character '1' is actually saved to entry field Notes.

New entries are properly synced if I copy it from another database (e.g. BIBTEX).

err_log.txt
log.txt

Apparently, JabRef constantly throws java.net.SocketTimeoutExceptions. See special errors when typing inputs at log excerpt below.

javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.705 CEST|null:-1|KeyLimit read side: algorithm = AES/GCM/NOPADDING:KEYUPDATE
countdown value = 137438953472
javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.706 CEST|null:-1|KeyLimit write side: algorithm = AES/GCM/NOPADDING:KEYUPDATE
countdown value = 137438953472
javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.755 CEST|null:-1|KeyLimit read side: algorithm = AES/GCM/NOPADDING:KEYUPDATE
countdown value = 137438953472
javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.757 CEST|null:-1|KeyLimit write side: algorithm = AES/GCM/NOPADDING:KEYUPDATE
countdown value = 137438953472
javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.918 CEST|null:-1|duplex close of SSLSocket
javax.net.ssl|DEBUG|1E|pool-4-thread-1|2020-06-30 15:34:39.921 CEST|null:-1|close the SSL connection (passive)