ungoogled-chromium: Segmentation Fault for Cosmic 71.0.3578.98-2

Describe the bug Running UC from Contributor Binaries fails with an error thrown by sandbox_linux.cc, followed by a segmentation fault.

Screenshots

[8110:8110:1130/174113.071502:ERROR:sandbox_linux.cc(379)] InitializeSandbox() called with multiple threads in process gpu-process.
Segmentation fault (core dumped)

Environment (please complete the following information):

• OS and version: Ubuntu 18.10 Cosmic
• ungoogled-chromium version: 70.0.3538.110-3