itstool has several problems with memory management with libxml2.  I'm
only skipping these languages because their XML causes our itstool to
crash.  Once that issue is fixed, this patch should be dropped and these
languages should be shipped again.

diff -ur mate-user-guide-1.26.0.orig/mate-user-guide/Makefile.am mate-user-guide-1.26.0/mate-user-guide/Makefile.am
--- mate-user-guide-1.26.0.orig/mate-user-guide/Makefile.am	2021-08-05 14:05:42.000000000 +0000
+++ mate-user-guide-1.26.0/mate-user-guide/Makefile.am	2021-11-27 23:57:00.019861763 +0000
@@ -75,7 +75,7 @@
 
 if USE_NLS
 # Add linguas to be ignored, e.g. IGNORE_HELP_LINGUAS = ca de es fr
-IGNORE_HELP_LINGUAS =
+IGNORE_HELP_LINGUAS = it ja kk sr
 HELP_LINGUAS = $(if $(IGNORE_HELP_LINGUAS), \
 	$(filter-out $(IGNORE_HELP_LINGUAS),$(subst /,,$(dir $(wildcard */*.po)))), \
 	$(subst /,,$(dir $(wildcard */*.po))) )