i don’t get the is_lobster_full_width() function in functions.php:365.
i expect it to be the switch if full-width was choosen at page creation. but there is no template in your theme, so it’s kind of useless.
but perhaps i am overlooking something?
i solved the problem with creating a child theme and added a templ-full-width.php.
in footer.php (child theme) i removed is_lobster_full_width():13 and replaced it with get_post_meta( get_the_ID(), '_wp_page_template', true ) != "templ-full-width.php". now, the sidebar is not displayed if i chose my newly created templ-full-width.php at page creation.