diff --git a/work/tech-design/data-url-new-tab-frame-load-interrupted.md b/work/tech-design/data-url-new-tab-frame-load-interrupted.md
index 52c95ffb..35d62c20 100644
--- a/work/tech-design/data-url-new-tab-frame-load-interrupted.md
+++ b/work/tech-design/data-url-new-tab-frame-load-interrupted.md
@@ -140,7 +140,10 @@ This prevents `createChildWebView` from returning a `WKWebView` to WebKit at all
   - Open a page that calls `window.open('javascript:void(0)', '_blank')`. Verify unchanged — still blocked.
   - Normal `window.open('https://example.com', '_blank')` continues to open in a new tab.
 
-- **Existing test coverage:** `PopupHandlingTabExtensionTests` should cover the `javascript:` scheme guard; extend to cover `data:` scheme.
+- **New unit tests needed:** `PopupHandlingTabExtensionTests` currently has no tests for the navigational-scheme guard in `createChildWebView`. Tests should be added to verify:
+  - `createWebView` returns `nil` for `javascript:` URLs.
+  - `createWebView` returns `nil` for `data:` URLs.
+  - `createWebView` returns a non-nil `WKWebView` for HTTPS URLs when popup permission is granted.
 
 - **Tab content state test:** verify that after a navigation to a `data:` URL is interrupted, `Tab.content` reflects the previous committed URL (or `.none`) rather than the blocked `data:` URL.