Actively maintained

Bootstrap API

provides hook_library support of the Javascript files of Twitter Bootstrap API.

Adds new image field type that is having the possibility to be annotated.

Max Professional Theme is a clean Drupal 7 theme.

A Responsive theme for a Corporate Website.

This module provides following styles for panels regions:
1. Horizontal Tab
2. Vertical Tab
3. Accordion
4. Grid
5. Slideshow

Bootstrap 5, Single Directory Components ,SASS subTheme, jQuery free.

The theme is ready for Drupal 11 and will work only for 10.3+ core versions.

Two subtheme options:

This base theme bridges the gap between Drupal and the Bootstrap Framework.

Columns
- Column based grid
- 1, 2 and 3 column automatic layouts
- User defined column widths
- Container and container fluid layout
Markup
- Standard Bootstrap 4 or 5 markup replacing Drupal twig templates
- Easy to customize twig templates
- Standard markup for header navigation
- Bootstrap 5 offcanvas menu
- Hide node titles on all view modes
- Multilevel main menu flyout submenus options
- Collapsed left slide main menu option
- Bootstrap form elements, including custom elements
- Classes to identify menu links
- Customized Bootstrap themed tables
- SVG icons integration on default links
- Scroll class on body on window scroll, with scroll up and down class added on scroll behaviour
- Three options for messages customizations
- Replace Commerce templates with Bootrstrap twig template
Features
- Color Module integration on subtheme
- Bootswatch integration via CDN
- Predefined Google Fonts combinations
- Card Column Views template to alllow card column listings
- Extra theme suggestions for entities and blocks
- Body classes for entities and views

No formal upgrade path, 5.x version is a complete rewrite of the original 8.x-3.x theme.
Open discussion here Path to upgrade Bootstrap Theme from version 8.x-3.x to 5.0.x

There is a new library being used for bootstrap 3 since release 3.33. The focus is on low impact improvements with minimal disruption.