In Symfony 2.6 we added a Bootstrap theme for Symfony Forms to easily style
all your forms based on Bootstrap, the most popular design framework. In
Symfony 3.4 we updated the form theme for Bootstrap 4, which was still a beta
version at that time.
Web accessibility is essential to create inclusive apps and services, and it’s
an integral part of our Symfony Diversity initiative. With much help from an
accessibility expert, Sandra, we have made the Bootstrap 4 from theme
compliant with the WCAG 2.0 standard.
The standard includes rules and guidelines to make content accessible for users
with disabilities, including impaired vision, learning disabilities and limited
In addition to minor tweaks and fixes, form errors are now rendered inside
<label> element to make sure there is a strong connection between the
error and its
<input>, as required by the WCAG 2.0 standard.
We’re working on a new documentation article about Bootstrap 4 and Symfony.
You can check the current proposal and suggest improvements or new contents.