[4.x]: BaseMultiSelectConditionRule mutates "New" option in select list

[nfourtythree]

What happened?

Description

When extending the BaseMultiSelectCondtionRule if there is a set of selectable options that include 'new' => 'New' the output of this value is mutated and an add icon is added.

Craft CMS version

4.2

PHP version

8.0

Operating system and version

No response

Database type and version

No response

Image driver and version

No response

Installed plugins and versions

No response

[brandonkelly]

Here’s the culprit:

cms/src/web/assets/cp/src/css/_main.scss

Lines 6243 to 6251 in fa36930

	body .selectize-dropdown-content > div[data-value='new']:before {
	@include icon;
	content: 'plus';
	margin-right: 5px;
	}
	body .selectize-dropdown-content > div[data-value='new']:after {
	content: '…';
	}

We’re not actually taking advantage of that anywhere in core, but it’s being used by Commerce, e.g. when creating a new tax rate:

I’m going to remove those styles in Craft 5. Anything still taking advantage of them should switch over to the _includes/forms/selectize.twig template (or craft\helpers\Cp::selectizeHtml() / selectizeFieldHtml()), and pass addOptionFn and addOptionLabel values to it. (See the _includes/forms/fs.twig template for an example.)

In the meantime, you will need to try to avoid using new as an option value. Ideally, a UID could be used instead, as handles can be fickle.