It's hard to belive it has been 7 years since I started working with Bootstrap! I started with Bootstrap 3, upgraded to Bootstrap 4 and now am happily using Bootstrap 5 in my designs. It is packed full of great features and 5.3.0 has introduced a lot of new, cool options.
Dark Mode Support
This offers opt-in by default option where you can easily set the whole page to a dark mode theme. Also cool is the ability to isolate the dark mode to just ceratin parent contaners on the page.
Custom Color Modes
Alongside the dark mode support is the ability to easily create custom color themes. You can create a custom theme color selector and then update your CSS variables.
New Link Helpers and Utilities
This new feature allows you to more easily add Bootstrap icons to links using styles. A new set of utilities to style links includes color opacity, underline offset, underline color, and underline opacity.
New Nav Underline
I think this is my favorite, an easy way to add a simple bottom border under the active nav link. So simple, but impactful and time saving!
If you are interested in learning more, you can read all about it on the Bootstrap blog.