diff --git a/packages/frontend/src/components/MkAsUi.vue b/packages/frontend/src/components/MkAsUi.vue
index d44e7724b3..c66e9d176a 100644
--- a/packages/frontend/src/components/MkAsUi.vue
+++ b/packages/frontend/src/components/MkAsUi.vue
@@ -106,7 +106,7 @@ const containerStyle = computed(() => {
 	const isBordered = c.borderWidth ?? c.borderColor ?? c.borderStyle;
 
 	const border = isBordered ? {
-		borderWidth: c.borderWidth ?? '1px',
+		borderWidth: `${c.borderWidth ?? 1}px`,
 		borderColor: c.borderColor ?? 'var(--MI_THEME-divider)',
 		borderStyle: c.borderStyle ?? 'solid',
 	} : undefined;