Make sure cover text is not affected by other paragraph font sizing.

apostrophe-2/css/editor-blocks.css

@@ -32,7 +32,7 @@
 	font-size: 19px;
 }
 
-.edit-post-visual-editor .editor-block-list__block p {
+.edit-post-visual-editor .editor-block-list__block p:not(.wp-block-cover-text) {
 	font-size: 19px;
 }