Running example test results in org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed]

[vogella]

Using:

Eclipse SDK Version: 2021-03 (4.19) Build id: I20210120-1800 OS: Linux, v.5.4.0-62-generic, x86_64 / gtk 3.24.20 Java version: 15

With the following features installed:

• RedDeer Eclipse Feature
• RedDeer SWT Feature
• RedDeer E4 Feature
• RedDeer UI Feature
• RedDeer Recorder Feature

I get the following error:

org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed]

Example project attached.

reddeer.zip