debian/changelog

+mate-utils (1.20.2-2) unstable; urgency=medium
+
+  * debian/rules:
+    + Don't build parallely. It fails. See upstream bug
+      https://github.com/mate-desktop/mate-utils/issues/211.
+      (Closes: #919058).
+
+ -- Mike Gabriel <sunweaver@debian.org>  Mon, 14 Jan 2019 10:55:46 +0100
+
 mate-utils (1.20.2-1) unstable; urgency=medium
 
   * New upstream release.

debian/rules

 #!/usr/bin/make -f
 
-DHFLAGS=--parallel
+DHFLAGS=--no-parallel
 
 export DEB_BUILD_MAINT_OPTIONS = hardening=+all
 DPKG_EXPORT_BUILDFLAGS = 1