Restrict the_post-navigation to same category?
Customize your posts navigation to get posts in the same tag. the_post_navigation( array( ‘prev_text’ => __( ‘prev chapter: %title’ ), ‘next_text’ => __( ‘next chapter: %title’ ), ‘in_same_term’ => true, ‘taxonomy’ => __( ‘post_tag’ ), ‘screen_reader_text’ => __( ‘Continue Reading’ ), ) ); Source