Under Ubuntu 19.10 (Mate), IDL 8.7.2. crashed with this interesting error:

# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x00007ff255a9e601, pid=32237, tid=0x00007ff276830700
#
# JRE version: OpenJDK Runtime Environment (Zulu 8.34.0.1-CA-linux64) (8.0_201-b10) (build 1.8.0_201-b10)
# Java VM: OpenJDK 64-Bit Server VM (25.201-b10 mixed mode linux-amd64 compressed oops)
# Problematic frame:
# C [libgobject-2.0.so.0+0x39601] g_type_check_instance_is_fundamentally_a+0x11
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /home/swisswuff/Downloads/hs_err_pid32237.log
Compiled method (nm) 6057 3501 n 0 org.eclipse.swt.internal.gtk.OS::_g_object_get_qdata (native)
total in heap [0x00007ff261d96990,0x00007ff261d96cf0] = 864
relocation [0x00007ff261d96ab8,0x00007ff261d96b00] = 72
main code [0x00007ff261d96b00,0x00007ff261d96ce8] = 488
oops [0x00007ff261d96ce8,0x00007ff261d96cf0] = 8
#
# If you would like to submit a bug report, please visit:
# http://www.azulsystems.com/support/
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.

Attempts:
- I tried to run ulimit -c unlimited before running idlde but same error (as above).
- I ran another desktop environment (Ubuntu default Gnome, instead of mate) and, no error. I ran mate again, same error.
- I then figured, no way, and worked my way through some of my installed GTK3-themes for windows borders etc.
(changed window border themes via: gnome-tweaks)
- turns out that some, but not all, GTK3-themes produce this error, regardless of what desktop environment I used, so...


Solution:
- logically I now run one of the themes that does not produce that error.