diff --git a/src/survey.ts b/src/survey.ts
index 283f8d1aa7..b79bb59792 100644
--- a/src/survey.ts
+++ b/src/survey.ts
@@ -3562,7 +3562,7 @@ export class SurveyModel extends SurveyElementCore
     return this.mode == "edit";
   }
   public get isDisplayMode(): boolean {
-    return this.mode == "display" || this.state == "preview";
+    return this.mode == "display" && !this.isDesignMode || this.state == "preview";
   }
   public get isUpdateValueTextOnTyping(): boolean {
     return this.textUpdateMode == "onTyping";
@@ -4735,7 +4735,7 @@ export class SurveyModel extends SurveyElementCore
       .append(this.css.root)
       .append(this.css.rootMobile, this.isMobile)
       .append(this.css.rootAnimationDisabled, !settings.animationEnabled)
-      .append(this.css.rootReadOnly, this.mode === "display")
+      .append(this.css.rootReadOnly, this.mode === "display" && !this.isDesignMode)
       .append(this.css.rootCompact, this.isCompact)
       .append(this.css.rootFitToContainer, this.fitToContainer)
       .toString();
diff --git a/tests/surveytests.ts b/tests/surveytests.ts
index e3b4e993f9..9adac7e3cb 100644
--- a/tests/surveytests.ts
+++ b/tests/surveytests.ts
@@ -19285,3 +19285,20 @@ QUnit.test("Advanced header title/description color", function (assert) {
   headerModel = headerLayoutElement.data as Cover;
   assert.equal(headerModel.headerClasses, "sv-header");
 });
+QUnit.test("Display mode in design time", function (assert) {
+  const survey = new SurveyModel();
+  assert.equal(survey.css.rootReadOnly, "sd-root--readonly");
+  assert.equal(survey.mode, "edit");
+  assert.equal(survey.isDisplayMode, false);
+  assert.equal(survey.getRootCss(), "sd-root-modern");
+
+  survey.mode = "display";
+  assert.equal(survey.mode, "display");
+  assert.equal(survey.isDisplayMode, true);
+  assert.ok(survey.getRootCss().indexOf(survey.css.rootReadOnly) !== -1);
+
+  survey.setDesignMode(true);
+  assert.equal(survey.mode, "display");
+  assert.equal(survey.isDisplayMode, false);
+  assert.equal(survey.getRootCss(), "sd-root-modern");
+});