diff --git a/src/components/ReadBookPage.tsx b/src/components/ReadBookPage.tsx
index 00c26a81..7a4b4ca3 100644
--- a/src/components/ReadBookPage.tsx
+++ b/src/components/ReadBookPage.tsx
@@ -315,6 +315,7 @@ const ReadBookPage: React.FunctionComponent<IReadBookPageProps> = (props) => {
                         border: none;
                         width: 100%;
                         height: 100%;
+                        display: block; // Prevent a 4px white bar at the bottom of the iframe. See BL-14065.
                     `}
                     src={iframeSrc}
                     //src={"https://google.com"}