diff --git a/packages/core/src/vivliostyle/vgen.ts b/packages/core/src/vivliostyle/vgen.ts
index 5521cda9e..9a939b012 100644
--- a/packages/core/src/vivliostyle/vgen.ts
+++ b/packages/core/src/vivliostyle/vgen.ts
@@ -2647,7 +2647,7 @@ export class ViewFactory
     const checkForcedLineBreakElem = (elem1: Element): boolean | null => {
       const { display, position, float } =
         this.viewport.window.getComputedStyle(elem1);
-      if (elem1.localName === "ruby") {
+      if (elem1.localName === "ruby" || Base.mediaTags[elem1.localName]) {
         return false;
       }
       if (elem1.localName === "br") {