Hide the struct tree layer during zooming

web/pdf_page_view.js

@@ -417,6 +417,7 @@ class PDFPageView {
     if (treeDom) {
       this.canvas?.append(treeDom);
     }
+    this.structTreeLayer?.show();
   }
 
   async #buildXfaTextContentItems(textDivs) {
@@ -505,6 +506,7 @@ class PDFPageView {
     if (textLayerNode) {
       this.textLayer.hide();
     }
+    this.structTreeLayer?.hide();
 
     if (!zoomLayerNode) {
       if (this.canvas) {
@@ -776,6 +778,7 @@ class PDFPageView {
     if (this.textLayer) {
       if (hideTextLayer) {
         this.textLayer.hide();
+        this.structTreeLayer?.hide();
       } else if (redrawTextLayer) {
         this.#renderTextLayer();
       }

web/pdf_viewer.css

@@ -149,6 +149,10 @@
   display: block;
 }
 
+.pdfViewer .page canvas .structTree {
+  contain: strict;
+}
+
 .pdfViewer .page canvas[hidden] {
   display: none;
 }

web/struct_tree_layer_builder.js

@@ -87,6 +87,18 @@ class StructTreeLayerBuilder {
     return (this.#treeDom = treeDom);
   }
 
+  hide() {
+    if (this.#treeDom && !this.#treeDom.hidden) {
+      this.#treeDom.hidden = true;
+    }
+  }
+
+  show() {
+    if (this.#treeDom?.hidden) {
+      this.#treeDom.hidden = false;
+    }
+  }
+
   #setAttributes(structElement, htmlElement) {
     if (structElement.alt !== undefined) {
       htmlElement.setAttribute("aria-label", structElement.alt);