diff --git a/backup/moodle2/backup_qtype_stack_plugin.class.php b/backup/moodle2/backup_qtype_stack_plugin.class.php
index 37dc9a4ecde6a66beffce23fd8239db8b356b2c6..383c8ed159aaf7cd52c7b5fb775add9597bd3d75 100644
--- a/backup/moodle2/backup_qtype_stack_plugin.class.php
+++ b/backup/moodle2/backup_qtype_stack_plugin.class.php
@@ -47,6 +47,7 @@ class backup_qtype_stack_plugin extends backup_qtype_plugin {
         $stackoptions = new backup_nested_element('stackoptions', ['id'],
                 [
                     'stackversion', 'questionvariables', 'specificfeedback', 'specificfeedbackformat',
+                    'questiondescription', 'questiondescriptionformat',
                     'questionnote', 'questionnoteformat', 'questionsimplify', 'assumepositive', 'assumereal',
                     'prtcorrect', 'prtcorrectformat', 'prtpartiallycorrect', 'prtpartiallycorrectformat',
                     'prtincorrect', 'prtincorrectformat',
diff --git a/stack/cas/parsingrules/996_call_modification.filter.php b/stack/cas/parsingrules/996_call_modification.filter.php
index 59717b122ca3b3d01c9a13e5cf22e6ac5d905f94..83c5d6fc3e80d4c5e2b561cbfe3f2d625a4fd8c7 100644
--- a/stack/cas/parsingrules/996_call_modification.filter.php
+++ b/stack/cas/parsingrules/996_call_modification.filter.php
@@ -87,7 +87,7 @@ class stack_ast_filter_996_call_modification implements stack_cas_astfilter {
 
                 // The order of these ifs is critical, we build up the checks
                 // so that no basic check gets lost due to more advanced ones
-                // doing more conplex things. The advanced cases assume that
+                // doing more complex things. The advanced cases assume that
                 // the simpler ones have been done already.
                 if (!($node->parentnode instanceof MP_Group) ||
                     $node->parentnode->items[0]->toString() !== $namecheck->toString()) {