JabRef version
JabRef 5.0-dev--snapshot--2019-03-16--master--d7dd41b00
Linux 4.15.0-46-generic amd64
Java 1.8.0_201

on Linux Mint 19.1

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

Steps to reproduce the behavior:

1. open Options/Preferences/BibTeX key generator
2. set the key to "[auth4:lower]-[year]"
3. In the entry editor, using ctrl+G to create the key produces output without the hyphen. E.g., "smit2019" instead of the expected "smit-2019".

It worked fine in JabRef 5.0 dev until recently, and it works in older version of JR.