diff --git a/web/app/components/header/account-setting/model-provider-page/model-selector/__tests__/index.spec.tsx b/web/app/components/header/account-setting/model-provider-page/model-selector/__tests__/index.spec.tsx
index 8ba2f095005..88d50e4b99f 100644
--- a/web/app/components/header/account-setting/model-provider-page/model-selector/__tests__/index.spec.tsx
+++ b/web/app/components/header/account-setting/model-provider-page/model-selector/__tests__/index.spec.tsx
@@ -108,10 +108,10 @@ describe('ModelSelector', () => {
       </>,
     )
 
-    expect(screen.getByRole('combobox', { name: 'System reasoning model' })).toBeInTheDocument()
+    expect(screen.getByRole('button', { name: 'System reasoning model' })).toBeInTheDocument()
   })
 
-  it('exposes required and invalid field guidance on the combobox trigger', () => {
+  it('exposes required and invalid field guidance on the popover trigger', () => {
     renderWithQueryClient(
       <>
         <span id="embedding-model-label">Embedding model</span>
@@ -126,10 +126,9 @@ describe('ModelSelector', () => {
       </>,
     )
 
-    const trigger = screen.getByRole('combobox', { name: 'Embedding model' })
+    const trigger = screen.getByRole('button', { name: /Embedding model/ })
     expect(trigger).toHaveAccessibleDescription('Select an embedding model.')
-    expect(trigger).toHaveAttribute('aria-invalid', 'true')
-    expect(trigger).toHaveAttribute('aria-required', 'true')
+    expect(trigger).toHaveAccessibleName(/common\.errorMsg\.fieldRequired/)
   })
 
   it('should toggle popup and close it after selecting a model', () => {
diff --git a/web/app/components/header/account-setting/model-provider-page/model-selector/model-selector-trigger.tsx b/web/app/components/header/account-setting/model-provider-page/model-selector/model-selector-trigger.tsx
index e5238e0c627..47be1ed5aa5 100644
--- a/web/app/components/header/account-setting/model-provider-page/model-selector/model-selector-trigger.tsx
+++ b/web/app/components/header/account-setting/model-provider-page/model-selector/model-selector-trigger.tsx
@@ -3,6 +3,7 @@ import { cn } from '@langgenius/dify-ui/cn'
 import { PopoverTrigger } from '@langgenius/dify-ui/popover'
 import { Tooltip, TooltipContent, TooltipTrigger } from '@langgenius/dify-ui/tooltip'
 import { useQuery } from '@tanstack/react-query'
+import { useId } from 'react'
 import { useTranslation } from 'react-i18next'
 import { consoleQuery } from '@/service/client'
 import {
@@ -50,6 +51,7 @@ function ModelSelectorTrigger({
   isModelCompatible = true,
 }: ModelSelectorTriggerProps) {
   const { t } = useTranslation()
+  const requiredTextId = useId()
 
   const isSelected = !!currentProvider && !!currentModel
   const isDeprecated = !isSelected && !!defaultModel
@@ -95,6 +97,13 @@ function ModelSelectorTrigger({
       : isSelected && ((!isActive && statusI18nKey) || !isModelCompatible)
         ? tooltipLabel
         : undefined
+  const configureModelLabel = t(($) => $['detailPanel.configureModel'], { ns: 'plugin' })
+  const requiredText = ariaRequired
+    ? t(($) => $['errorMsg.fieldRequired'], { field: '', ns: 'common' }).trim()
+    : undefined
+  const triggerLabelledBy = [ariaLabelledBy, requiredText ? requiredTextId : undefined]
+    .filter(Boolean)
+    .join(' ')
 
   return (
     <Tooltip>
@@ -110,9 +119,9 @@ function ModelSelectorTrigger({
                 aria-label={
                   ariaLabelledBy
                     ? undefined
-                    : t(($) => $['detailPanel.configureModel'], { ns: 'plugin' })
+                    : [configureModelLabel, requiredText].filter(Boolean).join(' ')
                 }
-                aria-labelledby={ariaLabelledBy}
+                aria-labelledby={triggerLabelledBy || undefined}
                 data-deprecated={isDeprecated ? '' : undefined}
                 data-invalid={ariaInvalid ? '' : undefined}
                 data-model-status={status}
@@ -137,6 +146,11 @@ function ModelSelectorTrigger({
               />
             }
           >
+            {requiredText && (
+              <span id={requiredTextId} className="sr-only">
+                {requiredText}
+              </span>
+            )}
             <span className="flex min-w-0 grow items-center gap-0.5">
               {isEmpty ? (
                 <span
@@ -182,7 +196,7 @@ function ModelSelectorTrigger({
                 )}
                 {isEmpty && (
                   <span className="grow truncate text-[13px] text-components-input-text-placeholder">
-                    {t(($) => $['detailPanel.configureModel'], { ns: 'plugin' })}
+                    {configureModelLabel}
                   </span>
                 )}
 
diff --git a/web/features/new-rag/__tests__/knowledge-settings-form.spec.tsx b/web/features/new-rag/__tests__/knowledge-settings-form.spec.tsx
index 4b2a98b2b73..8a9f6f97be2 100644
--- a/web/features/new-rag/__tests__/knowledge-settings-form.spec.tsx
+++ b/web/features/new-rag/__tests__/knowledge-settings-form.spec.tsx
@@ -121,13 +121,12 @@ vi.mock('@/app/components/header/account-setting/model-provider-page/model-selec
       <>
         <button
           type="button"
-          role="combobox"
           aria-controls={popupId}
           aria-expanded="false"
           aria-describedby={ariaDescribedBy}
-          aria-invalid={ariaInvalid || undefined}
           aria-labelledby={ariaLabelledBy}
-          aria-required={ariaRequired}
+          data-invalid={ariaInvalid ? '' : undefined}
+          data-required={ariaRequired ? '' : undefined}
           disabled={disabled}
           onClick={() =>
             onValueChange?.({
@@ -400,7 +399,7 @@ describe('KnowledgeSettingsForm', () => {
     const apiAccessSwitch = screen.getByRole('switch', {
       name: 'dataset.newKnowledge.apiAgentAccess',
     })
-    const reasoningSelector = screen.getByRole('combobox', {
+    const reasoningSelector = screen.getByRole('button', {
       name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
     })
     expect(apiAccessSwitch).not.toHaveAttribute('aria-disabled', 'true')
@@ -828,7 +827,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
@@ -903,7 +902,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.embeddingModelLabel',
       }),
     )
@@ -993,13 +992,12 @@ describe('KnowledgeSettingsForm', () => {
     expect(
       screen.queryByRole('switch', { name: 'common.modelProvider.rerankModel.key' }),
     ).not.toBeInTheDocument()
-    const rerankSelector = screen.getByRole('combobox', {
+    const rerankSelector = screen.getByRole('button', {
       name: 'common.modelProvider.rerankModel.key',
     })
     expect(rerankSelector).toHaveAccessibleDescription(
       'dataset.newKnowledge.settings.rerankModelRequired',
     )
-    expect(rerankSelector).toHaveAttribute('aria-invalid', 'true')
     await user.click(rerankSelector)
 
     await waitFor(() => expect(serviceMock.patchSettings).toHaveBeenCalledOnce())
@@ -1040,7 +1038,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
@@ -1066,10 +1064,10 @@ describe('KnowledgeSettingsForm', () => {
     const onDraftStart = vi.fn()
     renderForm({ onDraftFinish, onDraftStart })
 
-    const reasoningSelector = screen.getByRole('combobox', {
+    const reasoningSelector = screen.getByRole('button', {
       name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
     })
-    const rerankSelector = screen.getByRole('combobox', {
+    const rerankSelector = screen.getByRole('button', {
       name: 'common.modelProvider.rerankModel.key',
     })
     await user.click(reasoningSelector)
@@ -1160,10 +1158,10 @@ describe('KnowledgeSettingsForm', () => {
     })
     renderForm()
 
-    const reasoningSelector = screen.getByRole('combobox', {
+    const reasoningSelector = screen.getByRole('button', {
       name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
     })
-    const rerankSelector = screen.getByRole('combobox', {
+    const rerankSelector = screen.getByRole('button', {
       name: 'common.modelProvider.rerankModel.key',
     })
     await act(async () => {
@@ -1233,7 +1231,7 @@ describe('KnowledgeSettingsForm', () => {
       renderForm()
 
       await userEvent.setup({ advanceTimers: vi.advanceTimersByTime }).click(
-        screen.getByRole('combobox', {
+        screen.getByRole('button', {
           name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
         }),
       )
@@ -1359,28 +1357,24 @@ describe('KnowledgeSettingsForm', () => {
     expect(screen.getByRole('status')).toHaveTextContent(
       'datasetSettings.form.embeddingModel · common.modelProvider.systemReasoningModel.key · common.modelProvider.rerankModel.key',
     )
-    const reasoningSelector = screen.getByRole('combobox', {
+    const reasoningSelector = screen.getByRole('button', {
       name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
     })
     expect(reasoningSelector).toHaveAccessibleDescription(
       'dataset.newKnowledge.settings.systemReasoningModelRequired',
     )
-    expect(reasoningSelector).toHaveAttribute('aria-invalid', 'true')
-    expect(reasoningSelector).toHaveAttribute('aria-required', 'true')
-    const embeddingSelector = screen.getByRole('combobox', {
+    const embeddingSelector = screen.getByRole('button', {
       name: 'dataset.newKnowledge.settings.embeddingModelLabel',
     })
     expect(embeddingSelector).toHaveAccessibleDescription(
       'dataset.newKnowledge.settings.embeddingModelRequired',
     )
-    expect(embeddingSelector).toHaveAttribute('aria-invalid', 'true')
-    const rerankSelector = screen.getByRole('combobox', {
+    const rerankSelector = screen.getByRole('button', {
       name: 'common.modelProvider.rerankModel.key',
     })
     expect(rerankSelector).toHaveAccessibleDescription(
       'dataset.newKnowledge.settings.rerankModelRequired',
     )
-    expect(rerankSelector).toHaveAttribute('aria-invalid', 'true')
     expect(
       screen.getByRole('switch', { name: 'dataset.newKnowledge.apiAgentAccess' }),
     ).toHaveAttribute('aria-disabled', 'true')
@@ -1389,7 +1383,7 @@ describe('KnowledgeSettingsForm', () => {
     ).toHaveAttribute('aria-disabled', 'true')
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
@@ -1525,7 +1519,7 @@ describe('KnowledgeSettingsForm', () => {
     })
 
     expect(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     ).toBeInTheDocument()
@@ -1536,7 +1530,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
@@ -1593,7 +1587,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
@@ -1645,7 +1639,7 @@ describe('KnowledgeSettingsForm', () => {
     renderForm()
 
     await user.click(
-      screen.getByRole('combobox', {
+      screen.getByRole('button', {
         name: 'dataset.newKnowledge.settings.systemReasoningModelLabel',
       }),
     )
diff --git a/web/features/new-rag/create-connected-source-setup.tsx b/web/features/new-rag/create-connected-source-setup.tsx
index f35ccc5b3b5..f1721aed073 100644
--- a/web/features/new-rag/create-connected-source-setup.tsx
+++ b/web/features/new-rag/create-connected-source-setup.tsx
@@ -338,7 +338,6 @@ export function CreateConnectedSourceSetup({
           disabled={disabled}
           draft={draft}
           preventSubmitOnEnter
-          size="medium"
           onDraftChange={onDraftChange}
         />
         <SourceSyncPolicyField
diff --git a/web/features/new-rag/create-source-setup.tsx b/web/features/new-rag/create-source-setup.tsx
index fa58f893600..3bdd5bb13cf 100644
--- a/web/features/new-rag/create-source-setup.tsx
+++ b/web/features/new-rag/create-source-setup.tsx
@@ -506,7 +506,6 @@ export function CreateSourceSetup({
                 disabled={disabled}
                 draft={draft}
                 preventSubmitOnEnter
-                size="large"
                 onDraftChange={updateDraft}
               />
             }