Migli

Add a Bootstrap toolbar to WordPress editor, access to visual editors to create/edit :
<ul>
<li>Button (+ icons)</li>
<li>Icon</li>
<li>Table</li>
<li>Template (create only)</li>
<li>Breadcrumb</li>
<li>Pagination</li>
<li>Pager</li>
<li>Label</li>
<li>Badge</li>
<li>Alert</li>
<li>Panel</li>
<li>Snippet</li>
<li>Modal</li>
<li>Carousel</li>
<li>Navbar</li>
<li>Popover</li>
<li>Accordion</li>
<li>Jumbotron</li>
</ul>
Can be used with any WordPress theme : if your theme is based on Bootstrap, just check option to use your theme in WordPress editor. 
Otherwise, you can add default or custom Bootstrap css, including only needed elements.
Each element on Tiny Bootstrap Elements toolbar can be toggled individually.
Each element is customizable with usual Bootstrap options. Total Font Awesome support.
Use your own Bootstrap css, wich will be directly rendered either in your public pages, WordPress editor and plugin visual editors.
<pre><code>13 plugins in 1
Visual Editors
Lightweight plugin, adds only the needed css on pageload
Easy to install, no skill needed
</code></pre>
PRO version available at <a href="http://codecanyon.net/item/tinymce-bootstrap-plugin-for-wordpress/10293837" rel="nofollow ugc">http://codecanyon.net/item/tinymce-bootstrap-plugin-for-wordpress/10293837</a>
<h3>Support</h3>
You can file <a href="https://wordpress.org/support/plugin/tiny-bootstrap-elements-light" rel="ugc">support tickets</a> and post reviews here at the plugin repository.

Tiny Bootstrap Elements Light

Sucks!! Just a bate

Default settings add only unusable buttons to Tinymce that tell you to buy the pro version; you have to go enable the free options, and you can't disable the unusable ones.
There is no way to edit the content of accordion panels, add new panels or tab buttons, etc.
It is impossible to add regular text after a bootstrap div if it's the last element of content without changing over to code view.
I didn't explore it thoroughly because it was a truly terrible experience in the first 5 minutes. I am glad this free version was available to test out, though, because I saw this first on CodeCanyon and was considering buying it.



Snippets don't work

Tiny Bootstrap Elements Light Plugin adds Bootstrap Toolbar to tinyMce Rich Text Editor. Add/Edit any Bootstrap element to your posts/pages

Raihanul Islam

Easily add unlimited alert boxes for the new WordPress block editor. This includes dismissible alert notices.
This plugin works only in the Gutenberg/Block editor. Please use WordPress 5.0 and above or the Gutenberg plugin for pre 5.0 WordPress installations.

Awesome Alert Blocks

Awesome Alert Blocks notices for the new WordPress block editor.

Tiny Bootstrap Elements Light vs Awesome Alert Blocks