remove heading sequence in header ID

src/data/extra/web/js/markdownit.js

@@ -317,7 +317,10 @@ class MarkdownIt extends VxWorker {
     }
 
     generateHeaderId(p_headerIds, p_str) {
-        let idBase = p_str.replace(/\s/g, '-').toLowerCase();
+        // Remove leading heading sequence.
+        let regExp = Utils.headingSequenceRegExp();
+        let idBase = p_str.replace(regExp, '');
+        idBase = idBase.replace(/\s/g, '-').toLowerCase();
         let id = idBase;
         let idx = 1;
         while (p_headerIds.has(id)) {

src/data/extra/web/js/nodelinemapper.js

@@ -46,7 +46,7 @@ class NodeLineMapper {
         this.headingNodes = this.container.querySelectorAll("h1, h2, h3, h4, h5, h6");
         let headings = [];
         let needSectionNumber = window.vxOptions.sectionNumberEnabled;
-        let regExp = /^\d(?:\.\d)*\.? /;
+        let regExp = Utils.headingSequenceRegExp();
         for (let i = 0; i < this.headingNodes.length; ++i) {
             let node = this.headingNodes[i];
             let headingContent = this.getHeadingContent(node);

src/data/extra/web/js/utils.js

@@ -109,4 +109,8 @@ class Utils {
         }
         return true;
     }
+
+    static headingSequenceRegExp() {
+        return /^\d(?:\.\d)*\.? /;
+    }
 }