fix(ui): unable to search for nested fields in WhereBuilder field selection (#11986)

### What?
Extract text from the React node label in WhereBuilder

### Why?
If you have a nested field in filter options, the label would show
correctly, but the search will not work

### How
By adding an `extractTextFromReactNode` function that gets text out of
React.node label

### Code setup:
```
{
      type: "collapsible",
      label: "Meta",
      fields: [
        {
          name: 'media',
          type: 'relationship',
          relationTo: 'media',
          label: 'Ferrari',
          filterOptions: () => {
            return {
              id: { in: ['67efdbc872ca925bc2868933'] },
            }
          }
        },
        {
          name: 'media2',
          type: 'relationship',
          relationTo: 'media',
          label: 'Williams',
          filterOptions: () => {
            return {
              id: { in: ['67efdbc272ca925bc286891c'] },
            }
          }
        },
      ],
    },
    
 ```
  
### Before:

https://github.com/user-attachments/assets/25d4b3a2-6ac0-476b-973e-575238e916c4

  
 ### After:

https://github.com/user-attachments/assets/92346a6c-b2d1-4e08-b1e4-9ac1484f9ef3

---------

Co-authored-by: Jacob Fletcher <jacobsfletch@gmail.com>

packages/ui/src/elements/WhereBuilder/Condition/index.tsx

@@ -141,6 +141,11 @@ export const Condition: React.FC<Props> = (props) => {
           <div className={`${baseClass}__field`}>
             <ReactSelect
               disabled={disabled}
+              filterOption={(option, inputValue) =>
+                ((option?.data?.plainTextLabel as string) || option.label)
+                  .toLowerCase()
+                  .includes(inputValue.toLowerCase())
+              }
               isClearable={false}
               onChange={handleFieldChange}
               options={reducedFields.filter((field) => !field.field.admin.disableListFilter)}

packages/ui/src/elements/WhereBuilder/reduceFields.tsx

@@ -4,6 +4,7 @@ import type { ClientField } from 'payload'
 
 import { getTranslation } from '@payloadcms/translations'
 import { fieldIsHiddenOrDisabled, fieldIsID, tabHasName } from 'payload/shared'
+import { renderToStaticMarkup } from 'react-dom/server'
 
 import type { ReducedField } from './types.js'
 
@@ -152,10 +153,15 @@ export const reduceFields = ({
           })
         : localizedLabel
 
+      // React elements in filter options are not searchable in React Select
+      // Extract plain text to make them filterable in dropdowns
+      const textFromLabel = extractTextFromReactNode(formattedLabel)
+
       const fieldPath = pathPrefix ? createNestedClientFieldPath(pathPrefix, field) : field.name
 
       const formattedField: ReducedField = {
         label: formattedLabel,
+        plainTextLabel: textFromLabel,
         value: fieldPath,
         ...fieldTypes[field.type],
         field,
@@ -168,3 +174,29 @@ export const reduceFields = ({
     return reduced
   }, [])
 }
+
+/**
+ * Extracts plain text content from a React node by removing HTML tags.
+ * Used to make React elements searchable in filter dropdowns.
+ */
+const extractTextFromReactNode = (reactNode: React.ReactNode): string => {
+  if (!reactNode) {
+    return ''
+  }
+  if (typeof reactNode === 'string') {
+    return reactNode
+  }
+
+  const html = renderToStaticMarkup(reactNode)
+
+  // Handle different environments (server vs browser)
+  if (typeof document !== 'undefined') {
+    // Browser environment - use actual DOM
+    const div = document.createElement('div')
+    div.innerHTML = html
+    return div.textContent || ''
+  } else {
+    // Server environment - use regex to strip HTML tags
+    return html.replace(/<[^>]*>/g, '')
+  }
+}

packages/ui/src/elements/WhereBuilder/types.ts

@@ -23,6 +23,7 @@ export type ReducedField = {
     label: string
     value: Operator
   }[]
+  plainTextLabel?: string
   value: Value
 }
 

test/admin/e2e/list-view/e2e.spec.ts

@@ -393,6 +393,24 @@ describe('List View', () => {
       await expect(page.locator(tableRowLocator)).toHaveCount(2)
     })
 
+    test('should search for nested fields in field dropdown', async () => {
+      await page.goto(postsUrl.list)
+
+      await openListFilters(page, {})
+
+      const whereBuilder = page.locator('.where-builder')
+      await whereBuilder.locator('.where-builder__add-first-filter').click()
+      const conditionField = whereBuilder.locator('.condition__field')
+      await conditionField.click()
+      await conditionField.locator('input.rs__input').fill('Tab 1 > Title')
+
+      await expect(
+        conditionField.locator('.rs__menu-list').locator('div', {
+          hasText: exactText('Tab 1 > Title'),
+        }),
+      ).toBeVisible()
+    })
+
     test('should allow to filter in array field', async () => {
       await createArray()
 

tsconfig.base.json

@@ -31,7 +31,7 @@
       }
     ],
     "paths": {
-      "@payload-config": ["./test/_community/config.ts"],
+      "@payload-config": ["./test/admin/config.ts"],
       "@payloadcms/admin-bar": ["./packages/admin-bar/src"],
       "@payloadcms/live-preview": ["./packages/live-preview/src"],
       "@payloadcms/live-preview-react": ["./packages/live-preview-react/src/index.ts"],