Appearance > Customize > Panes not Expanding after WP 5.8 update

Just getting started with WP in general and have been enjoying using your theme so far. My WP updated to 5.8 this morning and I suddenly wasn’t able to expand the panes like ‘Home Main Content Area >’ when clicking Appearance –> Customize. Not sure if this is a theme issue or Plugin issue (Gutentor – Gutenberg Blocks – Page Builder for Gutenberg Editor updated to v3.1.3)

The following error appears in the console when clicking…
customize-widgets.min.js?ver=54217cb151203a814dd21ea6d0b8763c:2 Uncaught TypeError: t.onChangeSectionExpanded is not a function
at customize-widgets.min.js:2
at Array.forEach (<anonymous>)
at Object.completeCallback (customize-widgets.min.js:2)
at Object.onChangeExpanded (customize-controls.min.js:2)
at Object.onChangeExpanded (customize-widgets.min.js:2)
at Object._toggleExpanded (customize-controls.min.js:2)
at Object.collapse (customize-controls.min.js:2)
at Function.<anonymous> (customize-controls.min.js:2)
at Object.<anonymous> (load-scripts.php:20)
at Function.each (load-scripts.php:2)

THanks