Elementor duplicates columns on collapse/expand

I am currently trying to use Elementor with a custom built theme and I am getting some really odd behaviour. If I am working in a section and I expand or collapse the Elementor widget list, it adds an additional column to the section. Additionally, if I click on the menu in the upper left of the elementor tools (for the global settings and such) it asks if I would like to delete the current column.

I have tested plugins and none appear to be conflicting. If I switch to the 2016 theme it works just fine, so the problem appears to be in my theme. Right now my page template consists of:

<?php get_header(); ?>
<main>
  <?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
    <?php the_content(); ?>
  <?php endwhile; endif; ?>
</main>
<aside role="navigation" <?php aside_class(); ?>>
  <?php get_module("nav", "site"); ?>
</aside>
<?php get_footer(); ?>

This displays the page with the correct sidebar in Elementor’s editor, but like I said, I get the weird duplicate and delete issues. So my questions are:

Has anyone else seen this weird duplication/delete issue?
What is the bare minimum template that Elementor needs in order to work?
Does anyone know of other possible issues I should be looking at within my theme?