A WordPress plugin that contains many blocks to build your RundizStrap theme, or you can use it with any Bootstrap 5 themes.
You can manually set CSS class(es) by referring to the Bootstrap document.
Supported custom HTML attributes like <code>data-*</code>, <code>aria-*</code> in most blocks.
Available blocks:
<ul>
<li>Customizable div</li>
<li>Layout container</li>
<li>Layout row</li>
<li>Layout column</li>
<li>Search (for navbar and anywhere else)</li>
<li>Pagination (for list posts)</li>
<li>Navbar container</li>
<li>Navbar toggler button (for responsive toggler)</li>
<li>Navbar responsive wrapper (collapse, offcanvas)</li>
<li>Navbar navigation (display menu items)</li>
<li>Button (link, or button)</li>
<li>Comment form</li>
<li>Post navigation (display next, previous post)</li>
</ul>
Tested up to PHP 8.5.
The original source code is on GitHub ( https://github.com/Rundiz-WP/rundizstrap-companion ). 
It contains the original source of blocks before compile/build and blocks that are already built, the build tools via Node package (package.json).

RundizStrap Companion

A plugin that contains blocks for the Bootstrap theme that help you customize your site in your style. All blocks are based on Bootstrap CSS.

Jory Hogeveen

As easy as it gets. Add column classes to widgets with a select box, check whether the widget is the first, and save!
I’ve built this plugin for the Genesis Framework, though it will work with any theme that uses the (old) Bootstrap column classes.
You can also add your own classes through various filters to use this plugin with your theme’s grid framework.
<h4>Compatibility (IMPORTANT!)</h4>
This plugin does NOT add CSS for these columns. It ONLY adds the column classes to your widgets. The actual CSS should be added in your theme.
<h4>Filter: `genesis_widget_column_classes`</h4>
Allows you to change the available column classes
Parameters: <code>array</code> Default column classes. 
Return: <code>array</code> Array of column classes.
<h4>Filter: `genesis_widget_column_classes_capability`</h4>
Change the capability required to modify column classes. 
Since 1.2.2
Default: <code>edit_theme_options</code> 
Parameters: <code>string</code> The default capability. 
Return: <code>string</code> The new capability.
<h4>Filter `genesis_widget_column_classes_select_multiple`</h4>
Allow multiple classes to be selected. 
Since 1.3 
Return: boolean.
You can use these filters inside your theme functions.php file or in a plugin. 
You can find me here:
<ul>
<li><a href="http://www.keraweb.nl/" title="Keraweb" rel="nofollow ugc">Keraweb</a></li>
<li><a href="https://github.com/JoryHogeveen/genesis-widget-column-classes/" rel="nofollow ugc">GitHub</a></li>
<li><a href="https://nl.linkedin.com/in/joryhogeveen" title="LinkedIn profile" rel="nofollow ugc">LinkedIn</a></li>
</ul>

RundizStrap Companion vs Genesis Widget Column Classes