diff --git a/theme/boost/scss/moodle/drawer.scss b/theme/boost/scss/moodle/drawer.scss
index 90030e216ad..88a924dadf5 100644
--- a/theme/boost/scss/moodle/drawer.scss
+++ b/theme/boost/scss/moodle/drawer.scss
@@ -47,6 +47,17 @@ $drawer-bg: $gray-lighter !default;
 #nav-drawer {
     right: auto;
     left: 0;
+
+    /* Override the z-indexes defined in bootstrap/_list-group.scss that
+       lead to side effects on the user tours positioning. */
+    .list-group-item-action.active,
+    .list-group-item.active {
+        z-index: inherit;
+    }
+    .list-group-item-action.active + .list-group-item,
+    .list-group-item.active + .list-group-item {
+        border-top: none;
+    }
 }
 #page {
     margin-top: $fixed-header-y;
diff --git a/theme/boost/style/moodle.css b/theme/boost/style/moodle.css
index 9d351158aa3..3cc2e83466e 100644
--- a/theme/boost/style/moodle.css
+++ b/theme/boost/style/moodle.css
@@ -12602,7 +12602,15 @@ span.editinstructions {
 
 #nav-drawer {
   right: auto;
-  left: 0; }
+  left: 0;
+  /* Override the z-indexes defined in bootstrap/_list-group.scss that
+       lead to side effects on the user tours positioning. */ }
+  #nav-drawer .list-group-item-action.active,
+  #nav-drawer .list-group-item.active {
+    z-index: inherit; }
+  #nav-drawer .list-group-item-action.active + .list-group-item,
+  #nav-drawer .list-group-item.active + .list-group-item {
+    border-top: none; }
 
 #page {
   margin-top: 50px; }
diff --git a/theme/classic/style/moodle.css b/theme/classic/style/moodle.css
index c28589ff5c3..8fc9102ad82 100644
--- a/theme/classic/style/moodle.css
+++ b/theme/classic/style/moodle.css
@@ -12849,7 +12849,15 @@ span.editinstructions {
 
 #nav-drawer {
   right: auto;
-  left: 0; }
+  left: 0;
+  /* Override the z-indexes defined in bootstrap/_list-group.scss that
+       lead to side effects on the user tours positioning. */ }
+  #nav-drawer .list-group-item-action.active,
+  #nav-drawer .list-group-item.active {
+    z-index: inherit; }
+  #nav-drawer .list-group-item-action.active + .list-group-item,
+  #nav-drawer .list-group-item.active + .list-group-item {
+    border-top: none; }
 
 #page {
   margin-top: 50px; }