Feature Request: Implementing Percentage (%) Prefix and @extend Support for Bootstrap Classes

[maikycourse]

I use Bootstrap with SCSS, and many times, instead of applying all the classes to a tag like:
<p class="fs-5 fw-semibold text-secondary text-opacity-75">
I prefer to create my custom class .text-subtitle and use @extend so that the HTML becomes less cluttered, and the .text-subtitle class inherits the properties I want from Bootstrap classes.

I would like Bootstrap to implement all the classes it has with % in addition to .. For example:

.fw-bold, %fw-bold {
  font-weight: bold;
}

Then, after generating the CSS file and using PurgeCSS, it will be cleaner if I use:

.my-custom-class {
  @extend %fw-bold;
}

instead of:

.my-custom-class {
  @extend .fw-bold;
}

This change will make the CSS file smaller and more efficient, resulting in a better development experience.