I'm using yEd for Linux and get regular UI freezes for 10-20 seconds.
The system becomes completely unresponsive for that time, but than it gets back to usable state. Freezing occurs again and again during the same yEd working session.
Switching to different JVMs doesn't solve the issue.
The workaround which works for me is to run yEd for Windows in the VisualVM virtual machine, on the same hardware where Linux runs. In that case freezing never occurs.
Linux Mint 18.3 Sylvia
$ cat /proc/version
Linux version 4.15.0-47-generic (buildd@lgw01-amd64-028) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.10)) #50~16.04.1-Ubuntu SMP Fri Mar 15 16:06:21 UTC 2019
1) built-in Java 8 for yEd 3.18.2
2) built-in Java 10 for yEd 3.18.2
3) built-in Java 11 for yEd 3.19
4) local Java 8 (Oracle): Java(TM) SE Runtime Environment (build 1.8.0_201-b09)