themes-wordpress/blockbase/sass/blocks/_paragraph.scss

// Needed until https://github.com/WordPress/gutenberg/issues/36122 is fixed
p {

	&.has-drop-cap:not(:focus)::first-letter {
		font-size: var(--wp--custom--paragraph--dropcap--typography--font-size);
		font-weight: var(--wp--custom--paragraph--dropcap--typography--font-weight);
		margin: var(--wp--custom--paragraph--dropcap--margin);
	}
}