cURL error with Frontity Embedded Mode

I’m working on a project locally with Varying Vagrant Vagrants and the local dev task. When I Install the latest Frontity Embedded Mode plugin and following the configuration steps on this page, I get the following error:

Fatal error: Uncaught Exception: cURL error 7: Failed to connect to localhost port 3000: Connection refused in /srv/www/shoreline-mv/public_html/wp-content/plugins/frontity-embedded-master/includes/template.php:83 Stack trace: #0 /srv/www/shoreline-mv/public_html/wp-includes/template-loader.php(106): include() #1 /srv/www/shoreline-mv/public_html/wp-blog-header.php(19): require_once('/srv/www/shorel...') #2 /srv/www/shoreline-mv/public_html/index.php(17): require('/srv/www/shorel...') #3 {main} thrown in /srv/www/shoreline-mv/public_html/wp-content/plugins/frontity-embedded-master/includes/template.php on line 83

I can access the Frontity project on http://localhost:3000 and am running the dev task by the following commend:

npx frontity dev --public-path http://localhost:3000/static

The Frontity Embedded Mode plugin is set to the URL http://localhost:3000.

I’ve tried running the WordPress server with and without https and that doesn’t make a difference.

Here’s my npx frontity info output:

## System:
 - OS: Linux 5.11 Pop!_OS 21.04
 - CPU: (16) x64 AMD Ryzen 7 PRO 4750G with Radeon Graphics
 - Memory: 12.66 GB / 30.83 GB
 - Shell: 3.3.1 - /usr/bin/fish
## Binaries:
 - Node: 14.17.0 - ~/n/bin/node
 - npm: 6.14.13 - ~/n/bin/npm
## Browsers:
 - Chrome: 92.0.4515.131
 - Firefox: 91.0
## npmPackages:
 - @frontity/core: ^1.14.3 => 1.14.3 
 - @frontity/html2react: ^1.7.0 => 1.7.0 
 - @frontity/tiny-router: ^1.4.3 => 1.4.3 
 - @frontity/wp-source: ^1.11.5 => 1.11.5 
 - frontity: ^1.16.1 => 1.16.1 
 - shorelinemv-theme: file:packages/shorelinemv-theme => 1.0.0 
## npmGlobalPackages:
 - frontity: Not Found
 - npx: Not Found

WordPress is running version 5.8 (I just updated it). Could it be running WordPress in a VM is the problem?