Options Don’t Show on Underscores based custom theme

I am trying to use this plugin with a custom theme built on an Underscores starter theme. I set up a Woocommerce product with some radio button options and a text input. I enabled “Display Custom Options ..” and “Enable Price Calculation ..”
The only thing that shows on the front end is an empty div:

<div id="uni_cpo_options" class="uni-builderius-container"></div>

I switched the theme to Twenty Nineteen, and everything works, so it is something to do with the theme. I am wondering if you can help me figure out what is different with the themes so I can add or remove it in my custom theme and get it to work.

Thanks

• This topic was modified 5 years, 4 months ago by slaymakermkting.