By bnjmnm on
Change record status: 
Published (View all published change records)
Project: 
Drupal core
Introduced in branch: 
10.2.x
Introduced in version: 
10.2.0
Issue links: 
https://www.drupal.org/node/3380021
Description: 

This is a slight deviation from Stable 9's markup policy in order to facilitate better compatibility with contributed modules.
Stable 9 is a minimal base theme designed to provides only the markup necessary to achieve basic functionality. Part of this is adding very few classes, and for those added, prefixing them with js- to indicate they exist for JavaScript functionality, not styling. Until this change, this included form elements not having form-type-INPUT_TYPE classes, and only offering js-form-type-INPUT_TYPE classes for JavaScript targeting.

Although the js- prefixed selectors are what module JavaScript should be using, a significant enough number of modules target form-type-INPUT_TYPE instead, and thus do not work properly with Stable 9 extending themes. It was decided that instead of campaigning dozens/hundreds of modules to "do it right", Drupal core could make one small change and fix it for all of them.

WHAT THEMERS SHOULD WATCH OUT FOR
If your theme CSS has stray/unused styles targeting form-type-INPUT_TYPE, they will now be styling form elements on your page. It's probably worth grepping your site CSS for .form-type and see if there are any styles that might suddenly be "activated" as a result of this change.