Hello.
AbanteCart default template do not include less files.
No ****.
Check the changes you made with your clone template.
What changes?
I cloned a template within your Cart Software System, using a process you defined, to create and apply a new template extension. See process below.
What possible "changes to my clone template" could start calling for less files?
Possibly you load bootstrap in some wrong way and bootstrap trying to load this files https://stackoverflow.com/questions/35142485/why-is-bootstrap-trying-to-load-less-files-in-edge 
I didn't load bootstrap. Abantecart loaded bootstrap.
It's the same as when I build a joomla site: I install joomla and I start to do stuff. Some of the stuff I do is affected by bootstrap because joomla loaded bootstrap and joomla uses bootstrap.
But I didn't load bootstrap. I've never "loaded" bootstrap. It's just something that is loaded, called and used by CMS's that I use.
Remind me - at what point during an AbanteCart install does your software tell the user to go get some bootstrap and install some bootstrap in some certain folder?
When does that happen?
I know right? It never happens.
So that may mean that AbanteCart is fucking something up somewhere, right?
Where's the other guy?
The link you provided above references source mapping, possibly after minimizing. AC users don't do any source mapping or minimizing. They just diddle with style.css to change some colors. How does that lead to less file references that don't exist?
FYI: here is a cut-n-paste of the method I used to create the clone. Maybe you can see where there is a problem with this method?
To create a new template extension that uses a clone of the default template:
1.) Install Extension Development Tool:
a.
https://github.com/abantecart/developer_tools_extensionb. Use the green box to download zip file. Unzip the file into a new folder in your work area. It will have various versions of the developer_tools. Choose one.
c. For the chosen version of dev_tools, open the /code/extensions/ folder.
d. Copy the developer_tools directory from that folder to your AC extensions directory.
e. Go to the site backend Extensions / All Extensions tab. Locate developer_tools and click the button that looks like a play button to install the tools.
f. Then set the status of the tools extension to ON.
g. Now you should have a new "Extension Developer Tools" tab in the system section.
2.) Clone the default template (this will simultaneously create a new extension):
a. In Design / Templates, clone the Default template by clicking the double-square icon.
b. Select Clone to Extension.
c. Select Full Clone type so that it will include CSS, Javascripts etc.
d. Choose a name and unique identifier, then click Clone Template.
3.) Assign the new template clone to the new extension:
a. Go to Extensions / All Extensions - locate the newly created extension.
b. Click the Edit button to edit the new extension, click the Additional Settings tab.
c. On the upper left, select the new clone from the dropdown menu "Edit Template Settings".
d. Scroll down and click Save.
4.) Set the storefront to use the new template:
a. Go back to Design / Templates, click the "on / off" button of the new template to set it as the active storefront template.
5.) Begin editing the new template files.