diff --git a/src/core/annotation.js b/src/core/annotation.js
index a3d05f278..8fe95d88f 100644
--- a/src/core/annotation.js
+++ b/src/core/annotation.js
@@ -4920,7 +4920,7 @@ class StampAnnotation extends MarkupAnnotation {
   mustBeViewedWhenEditing(isEditing, modifiedIds = null) {
     if (isEditing) {
       if (!this.data.isEditable) {
-        return false;
+        return true;
       }
       // When we're editing, we want to ensure that the stamp annotation is
       // drawn on a canvas in order to use it in the annotation editor layer.
diff --git a/test/integration/freetext_editor_spec.mjs b/test/integration/freetext_editor_spec.mjs
index 29c24a487..84b886b70 100644
--- a/test/integration/freetext_editor_spec.mjs
+++ b/test/integration/freetext_editor_spec.mjs
@@ -28,7 +28,7 @@ import {
   getRect,
   getSerialized,
   hover,
-  isCanvasWhite,
+  isCanvasMonochrome,
   kbBigMoveDown,
   kbBigMoveLeft,
   kbBigMoveRight,
@@ -837,7 +837,7 @@ describe("FreeText Editor", () => {
           await switchToFreeText(page);
 
           // The page has been re-rendered but with no freetext annotations.
-          let isWhite = await isCanvasWhite(page, 1);
+          let isWhite = await isCanvasMonochrome(page, 1, null, 0xffffffff);
           expect(isWhite).withContext(`In ${browserName}`).toBeTrue();
 
           let editorIds = await getEditors(page, "freeText");
@@ -880,7 +880,7 @@ describe("FreeText Editor", () => {
           editorIds = await getEditors(page, "freeText");
           expect(editorIds.length).withContext(`In ${browserName}`).toEqual(1);
 
-          isWhite = await isCanvasWhite(page, 1, editorRect);
+          isWhite = await isCanvasMonochrome(page, 1, editorRect, 0xffffffff);
           expect(isWhite).withContext(`In ${browserName}`).toBeTrue();
 
           // Check we've now a div containing the text.
diff --git a/test/integration/ink_editor_spec.mjs b/test/integration/ink_editor_spec.mjs
index ea6634a5a..13000bfc4 100644
--- a/test/integration/ink_editor_spec.mjs
+++ b/test/integration/ink_editor_spec.mjs
@@ -23,7 +23,7 @@ import {
   getEditorSelector,
   getRect,
   getSerialized,
-  isCanvasWhite,
+  isCanvasMonochrome,
   kbRedo,
   kbUndo,
   loadAndWait,
@@ -747,7 +747,12 @@ describe("Ink Editor", () => {
           await switchToInk(page);
 
           // The page has been re-rendered but with no ink annotations.
-          let isWhite = await isCanvasWhite(page, 1, annotationsRect);
+          let isWhite = await isCanvasMonochrome(
+            page,
+            1,
+            annotationsRect,
+            0xffffffff
+          );
           expect(isWhite).withContext(`In ${browserName}`).toBeTrue();
 
           let editorIds = await getEditors(page, "ink");
@@ -781,7 +786,7 @@ describe("Ink Editor", () => {
           editorIds = await getEditors(page, "ink");
           expect(editorIds.length).withContext(`In ${browserName}`).toEqual(1);
 
-          isWhite = await isCanvasWhite(page, 1, editorRect);
+          isWhite = await isCanvasMonochrome(page, 1, editorRect, 0xffffffff);
           expect(isWhite).withContext(`In ${browserName}`).toBeTrue();
 
           // Check we've now a svg with a red stroke.
diff --git a/test/integration/stamp_editor_spec.mjs b/test/integration/stamp_editor_spec.mjs
index fbd153762..b76a84e79 100644
--- a/test/integration/stamp_editor_spec.mjs
+++ b/test/integration/stamp_editor_spec.mjs
@@ -30,6 +30,7 @@ import {
   getFirstSerialized,
   getRect,
   getSerialized,
+  isCanvasMonochrome,
   isVisible,
   kbBigMoveDown,
   kbBigMoveRight,
@@ -45,6 +46,7 @@ import {
   waitForAnnotationEditorLayer,
   waitForAnnotationModeChanged,
   waitForEntryInStorage,
+  waitForPageRendered,
   waitForSelectedEditor,
   waitForSerialized,
   waitForTimeout,
@@ -1819,4 +1821,57 @@ describe("Stamp Editor", () => {
       );
     });
   });
+
+  describe("Switch to edit mode, zoom and check that the non-editable stamp is still there", () => {
+    const annotationSelector = getAnnotationSelector("14R");
+
+    let pages;
+
+    beforeAll(async () => {
+      pages = await loadAndWait("red_stamp.pdf", annotationSelector, 20);
+    });
+
+    afterAll(async () => {
+      await closePages(pages);
+    });
+
+    it("must check if the canvas is still red", async () => {
+      await Promise.all(
+        pages.map(async ([, page]) => {
+          expect(
+            await isCanvasMonochrome(page, 1, null, 0xff0000ff)
+          ).toBeTrue();
+
+          await switchToStamp(page);
+
+          expect(
+            await isCanvasMonochrome(page, 1, null, 0xff0000ff)
+          ).toBeTrue();
+
+          const rectPage = await getRect(
+            page,
+            `.page[data-page-number = "1"] .annotationEditorLayer`
+          );
+
+          const handle = await waitForPageRendered(page, 1);
+          const originX = rectPage.x + rectPage.width / 2;
+          const originY = rectPage.y + rectPage.height / 2;
+          await page.evaluate(
+            origin => {
+              window.PDFViewerApplication.pdfViewer.increaseScale({
+                scaleFactor: 2,
+                origin,
+              });
+            },
+            [originX, originY]
+          );
+          await awaitPromise(handle);
+
+          expect(
+            await isCanvasMonochrome(page, 1, null, 0xff0000ff)
+          ).toBeTrue();
+        })
+      );
+    });
+  });
 });
diff --git a/test/integration/test_utils.mjs b/test/integration/test_utils.mjs
index 3d67f7fcd..97081516b 100644
--- a/test/integration/test_utils.mjs
+++ b/test/integration/test_utils.mjs
@@ -838,9 +838,9 @@ function waitForNoElement(page, selector) {
   );
 }
 
-function isCanvasWhite(page, pageNumber, rectangle) {
+function isCanvasMonochrome(page, pageNumber, rectangle, color) {
   return page.evaluate(
-    (rect, pageN) => {
+    (rect, pageN, col) => {
       const canvas = document.querySelector(
         `.page[data-page-number = "${pageN}"] .canvasWrapper canvas`
       );
@@ -853,10 +853,11 @@ function isCanvasWhite(page, pageNumber, rectangle) {
         rect.width,
         rect.height
       );
-      return new Uint32Array(data.buffer).every(x => x === 0xffffffff);
+      return new Uint32Array(data.buffer).every(x => x === col);
     },
     rectangle,
-    pageNumber
+    pageNumber,
+    color
   );
 }
 
@@ -925,7 +926,7 @@ export {
   getSpanRectFromText,
   getXY,
   hover,
-  isCanvasWhite,
+  isCanvasMonochrome,
   isVisible,
   kbBigMoveDown,
   kbBigMoveLeft,
diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index 624784981..900b36d08 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -710,3 +710,4 @@
 !bug1019475_2.pdf
 !issue19505.pdf
 !colors.pdf
+!red_stamp.pdf
diff --git a/test/pdfs/red_stamp.pdf b/test/pdfs/red_stamp.pdf
new file mode 100755
index 000000000..c76cdc942
Binary files /dev/null and b/test/pdfs/red_stamp.pdf differ