Posted by Wade Walker on Feb 19, 2019; 1:18am
URL: https://forum.jogamp.org/NewtCanvasSWT-Linux-Exception-with-GTK-VERSION-tp4039442p4039553.html

One thing I forgot to mention: you might try

export SWT_GTK3=0

 after (or instead of) your patch to SWTAccessor. It could be that GTK2 will work for you.