Where does the uses_bootstrap variable/setting get set?

I am building a custom theme and am looking at the base OpenEdX theme as I make my own templates and custom SCSS files. Currently, I’m making modifications to the footer and so I copied the template file from openedx > lms > static > templates > footer.html and placed it into my own custom theme in the appropriate directory. My version of the footer template loads properly. However, my question is about a conditional in that footer.html template that I copied over

% if uses_bootstrap:

The footer.html template displays two different versions of the footer depending on whether or not that uses_bootstrap variable is True or False. I’m wondering if there is a theme setting that I would change to True if I want the Bootstrap version of the footer or if it’s just something I would declare earlier in the template, e.g.

<% uses_bootstrap = True %>

According to my digging in the edx-platform source code, uses_bootstrap should be true most of the time: Search · uses_bootstrap · GitHub
So, this value is not defined by a setting. I honestly have no idea in which cases it becomes false. Maybe only some pages/views are bootstrap-compatible, and thus blocks that are referenced in multiple pages need to be compatible both with and without bootstrap?

Thanks @regis . I did a similar search through the edx-platform repository on Github before posting here. I thought the same thing as you that the default for uses_bootstrap could be True, but I when loading my custom theme with a copy of footer.html template from edx-platform and the dev server running, I was seeing the footer rendered on the front-end with markup that is supposed to display when uses_bootstrap is False. That’s what led me to post here.