diff --git a/.gitignore b/.gitignore
index b09e783d8358d1d97b3fc23cb8d13d9a2a93a84a..58ba886c5237a164561730790b8fe92ea5f46f0f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,3 +23,5 @@ npm-debug.log
 
 # mac files
 .DS_Store
+
+.tool-versions
diff --git a/templates/md/class.ejs b/templates/md/class.ejs
index 4274f90487961e55a7ffb92a64239dc91c7f045a..84307637b09217d254f0353545735494756d3c6d 100644
--- a/templates/md/class.ejs
+++ b/templates/md/class.ejs
@@ -21,7 +21,10 @@ layout: default
 ---
 <%
 function escape(s) {
-  return s.replace(/\r\n/g, '<br>').replace(/\n/g, '<br>');
+    if (s) {
+      return s.replace(/\r\n/g, '<br>').replace(/\n/g, '<br>');
+    }
+    return "";
 }
 %>
 # <%- clazz[consts.RDFS_LABEL] %>
@@ -31,4 +34,5 @@ function escape(s) {
 Note: <%- clazz[consts.SKOS_NOTE] %><% } %>
 |Name|JSON Name|Type|Description|Immutable|Mandatory|UserEditable|Note|Example Value|
 |--- |--- |--- |--- |--- |--- |--- |--- |--- |<% _.forEach(clazz.properties, function (prop) { %>
-| <%- prefixes.shrink(prop["@id"]) %> | <%- prop[consts.META_JSONNAME] %> | <%- model.datatypes[prop[consts.RDFS_RANGE]][consts.RDFS_LABEL] %> | <%- escape(prop[consts.RDFS_COMMENT]) %> | <%- escape(prop[consts.PROP_IMMUTABLE]) %> | <%- escape(prop[consts.PROP_MANDATORY]) %> | <%- escape(prop[consts.PROP_USEREDITABLE]) %> | <%- escape(prop[consts.SKOS_NOTE]) %> | <%- escape(prop[consts.SKOS_EXAMPLE]) %> | <% }); %>
+| <%- prefixes.shrink(prop["@id"]) %> | <%- prop[consts.META_JSONNAME] %> | <%- model.datatypes[prop[consts.RDFS_RANGE]][consts.RDFS_LABEL] %> | <%- escape(prop[consts.RDFS_COMMENT]) %> | <%- escape(prop[consts.PROP_IMMUTABLE]) %> | <%- escape(prop[consts.PROP_MANDATORY]) %> | <%- escape(prop[consts.PROP_USEREDITABLE]) %> | <%- escape(prop[consts.SKOS_NOTE]) %> | <%- escape(prop[consts.SKOS_EXAMPLE]) %> |
+<% }); %>