Our first stable v4 release! 🎉

Highlights:

• Brand new examples and overhauls for existing ones.
• Additional border utilities have been added and the default border-color for them darkened from $gray-200 to $gray-300.
• Pagination focus styles now match button and input focus state.
• Added responsive .order-0 classes to reset column order.
• Improved examples of form validation documentation by adding tooltip examples and more.
• New documentation added for using our CSS variables to the Theming page.
• Improved consistent across browsers when printing.
• Sass map extends and docs
• New and improved print display utilities

Project board

For more details, visit https://github.com/twbs/bootstrap/issues/25098.