What’s new in the Bootstrap web development framework

Bootstrap 4.3, the latest version of the Bootstrap web development framework, adds responsive font sizes, adds utilities, and deprecates code. A few details of the forthcoming Bootstrap Version 5 are also now available.

The open source Bootstrap uses JavaScript, HTML, and CSS for developing mobile-first websites. Developers can build applications using Sass variables and mixins, the Bootstrap grid system, and prebuilt components.

Where to download Bootstrap

You can download the production version of Bootstrap from GitHub.

Future version: What’s planned for Bootstrap Version 5

A big foundational change planned for Bootstap 5 is dropping the client-side dependency on jQuery for regular JavaScript. Other changes expected include:

• Moving to the open source Hugo static site generator from Jekyll. Dependencies will change to support this move.
• Improving branches for development, with master becoming the new v3-dev branch and v4-dev staying as is. There will be a new master branch to develop in Version 5.

Current version: What’s new in Bootstrap Version 4.3

Responsive font sizes automatically calculate the appropriate font size based on dimensions of the browser viewport or a visitor’s device. All font-size properties are switched to the @include fontsize() mixin. Bootstrap’s Stylelint configuration prevents the use of the font-size property with responsive font sizes. The new behavior is disabled by default; toggl it on via the $enable-responsive-font-sizes variable.

Other new features in Bootstrap 4.3 include:

• The text-break utility for applying word-break: break-word.
• The .stretched-link utility to make any anchor the size of its nearest position: relative parent, which is suitable for clickable cards.
• The .modal-dialog-scrollable modifier class to scroll content within a modal.
• Responsive .list-group-horizontal modifier classes to display list groups as a horizontal row.
• Smaller compiled CSS through the use of null for variables that by default inherit values from other elements.

The img-retina, invisible, float, and size mixins have been deprecated and will be removed in Boostrap Version 5.

Previous version: What’s new in Bootstrap Version 4.0

New features in Bootstrap Version 4.0, released in January 2018, include:

• Updates to print styles and utility classes, with printed pages now rendered to ensure reasonable sizing rather than being rendered as mobile devices. Also, print display utilities offer new display values to match standard display utilities.
• It is now easier to add borders or border subsets to components.
• Maps for the Sass CSS extension have been updated. Developers now can add, remove, or replace key-value pairs across CSS.
• Responsive classes have been added for greater control over the flexbox grid. These include the .order-0 and .order-last classes.
• Improvements to reuse and extension of variables.
• Code cleanup.

Bootstrap builders also have overhauled examples, which help developers use the framework. The Album example, for instance, has improved rendering and adds more content in photo cards. There’s also a new Pricing example, for building a pricing table.