Fix Disabled visual state ignored when Button has locally-set BackgroundColor/TextColor

[Dhivya-SF4094]

Note

Are you waiting for the changes in this PR to be merged?
It would be very helpful if you could test the resulting artifacts from this PR and let us know in a comment if this change resolves your issue. Thank you!

Issue Details

• Button with custom BackgroundColor and TextColor does not correctly apply the Disabled VisualState defined in Styles.xaml when IsEnabled=false.
• The issue occurs only when custom BackgroundColor and TextColor are set on the Button. Removing these custom values allows the Disabled VisualState to work correctly.

Root Cause

PR #18103 introduced a specificity downgrade for implicit-style VSM setters so that the Normal state cannot override locally-set values. This downgrade was correctly applied to the Normal state but inadvertently also prevented Disabled, Focused, and other non-Normal states from overriding locally-set values.

Description of Change

Added WithFullVsmPriority() to SetterSpecificity that promotes implicit VSM back to full VSM priority. In VisualStateManager.GoToState, this promotion is applied only when transitioning to non-Normal states, preserving the original #18103 behavior for Normal.

Validated the behaviour in the following platforms

• Android
• Windows
• iOS
• Mac

Issues Fixed:

Fixes #34363

Screenshots

Before	After
34363_BeforeFix.mov	34363_AfterFix.mov

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/dotnet/maui/main/eng/scripts/get-maui-pr.sh | bash -s -- 34444

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/dotnet/maui/main/eng/scripts/get-maui-pr.ps1) } 34444"

[Copilot]

Pull request overview

This PR fixes a regression where implicit-style VisualStateManager (VSM) setters for non-Normal states (e.g., Disabled) could no longer override locally-set Button values (e.g., BackgroundColor/TextColor) due to the implicit-VSM specificity downgrade introduced for #18103.

Changes:

• Add SetterSpecificity.WithFullVsmPriority() to promote implicit VSM specificity back to full VSM priority when needed.
• Update VisualStateManager.GoToState (and unapply paths) to promote specificity only for framework-driven (system) states, preserving the #18103 behavior for Normal.
• Add a regression unit test covering implicit-style Disabled state overriding a locally-set Button.BackgroundColor.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
src/Controls/src/Core/VisualStateManager.cs	Promotes implicit VSM specificity for selected system-driven states during apply/unapply.
src/Controls/src/Core/SetterSpecificity.cs	Adds helper to convert implicit-VSM specificity to full VSM specificity.
src/Controls/tests/Core.UnitTests/VisualStateManagerTests.cs	Adds regression test for implicit-style Disabled overriding a locally-set Button value.

[Copilot]

The comment says custom developer-defined states keep downgraded priority and references #34363, but this behavior is primarily about preserving the Normal-state/local-value precedence from #18103. Referencing #18103 here (or removing the issue number) would make the intent clearer and avoid tying the comment to the wrong issue.

Suggested change

	// Custom developer-defined states keep downgraded priority (#34363).
	// Custom developer-defined states keep downgraded priority to preserve Normal-state/local-value precedence (#18103).

[MauiBot]

🚦 Gate - Test Before and After Fix

📊 Expand Full Gate — 54499dc · Addressed copilot review concern

---

Gate Result: ✅ PASSED

Platform: ANDROID · Base: main · Merge base: 794a9fa6

Test	Without Fix (expect FAIL)	With Fix (expect PASS)
🧪 VisualStateManagerTests VisualStateManagerTests	✅ FAIL — 127s	✅ PASS — 79s

🔴 Without fix — 🧪 VisualStateManagerTests: FAIL ✅ · 127s

  Determining projects to restore...
  Restored /home/vsts/work/1/s/src/TestUtils/src/TestUtils/TestUtils.csproj (in 3.24 sec).
  Restored /home/vsts/work/1/s/src/Graphics/src/Graphics/Graphics.csproj (in 131 ms).
  Restored /home/vsts/work/1/s/src/Essentials/src/Essentials.csproj (in 2.45 sec).
  Restored /home/vsts/work/1/s/src/Core/src/Core.csproj (in 2.62 sec).
  Restored /home/vsts/work/1/s/src/Core/maps/src/Maps.csproj (in 8.72 sec).
  Restored /home/vsts/work/1/s/src/Controls/src/Xaml/Controls.Xaml.csproj (in 63 ms).
  Restored /home/vsts/work/1/s/src/Controls/src/Core/Controls.Core.csproj (in 30 ms).
  Restored /home/vsts/work/1/s/src/Controls/Maps/src/Controls.Maps.csproj (in 49 ms).
  Restored /home/vsts/work/1/s/src/Controls/tests/Core.UnitTests/Controls.Core.UnitTests.csproj (in 1.62 sec).
  1 of 10 projects are up-to-date for restore.
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  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
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  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
  Controls.Xaml -> /home/vsts/work/1/s/artifacts/bin/Controls.Xaml/Debug/net10.0/Microsoft.Maui.Controls.Xaml.dll
  Controls.Maps -> /home/vsts/work/1/s/artifacts/bin/Controls.Maps/Debug/net10.0/Microsoft.Maui.Controls.Maps.dll
  TestUtils -> /home/vsts/work/1/s/artifacts/bin/TestUtils/Debug/netstandard2.0/Microsoft.Maui.TestUtils.dll
  Controls.Core.UnitTests -> /home/vsts/work/1/s/artifacts/bin/Controls.Core.UnitTests/Debug/net10.0/Microsoft.Maui.Controls.Core.UnitTests.dll
Test run for /home/vsts/work/1/s/artifacts/bin/Controls.Core.UnitTests/Debug/net10.0/Microsoft.Maui.Controls.Core.UnitTests.dll (.NETCoreApp,Version=v10.0)
VSTest version 18.0.1 (x64)

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
[xUnit.net 00:00:00.00] xUnit.net VSTest Adapter v2.8.2+699d445a1a (64-bit .NET 10.0.0)
[xUnit.net 00:00:00.14]   Discovering: Microsoft.Maui.Controls.Core.UnitTests
[xUnit.net 00:00:01.44]   Discovered:  Microsoft.Maui.Controls.Core.UnitTests
[xUnit.net 00:00:01.45]   Starting:    Microsoft.Maui.Controls.Core.UnitTests
  Passed ElementsDoNotHaveVisualStateGroupsCollectionByDefault [16 ms]
  Passed StateNamesMustBeUniqueWithinGroupListWhenAddingGroup [3 ms]
  Passed VisualElementsStateGroupsAreDistinct [3 ms]
  Passed CustomImplicitStyleVSMStateDoesNotOverrideLocalValue [15 ms]
  Passed ChangingStyleContainingVSMShouldResetStateValue [3 ms]
  Passed AppThemeBindingInVSM [3 ms]
  Passed CanRemoveAGroupAndAddANewGroupWithTheSameName [< 1 ms]
  Passed InitialStateIsNormalIfAvailable [< 1 ms]
  Passed VisualElementGoesToCorrectStateWhenSetterHasTarget [4 ms]
[xUnit.net 00:00:01.56]     ValidatePerformance [SKIP]
[xUnit.net 00:00:01.56]       This test was created to check performance characteristics; leaving it in because it may be useful again.
[xUnit.net 00:00:01.58]       Assert.Equal() Failure: Values differ
[xUnit.net 00:00:01.58]       Expected: [Color: Red=0.5019608, Green=0.5019608, Blue=0.5019608, Alpha=1]
[xUnit.net 00:00:01.58]       Actual:   [Color: Red=1, Green=0, Blue=0, Alpha=1]
[xUnit.net 00:00:01.58]       Stack Trace:
[xUnit.net 00:00:01.58]         /_/src/Controls/tests/Core.UnitTests/VisualStateManagerTests.cs(594,0): at Microsoft.Maui.Controls.Core.UnitTests.VisualStateManagerTests.ImplicitStyleDisabledVSMOverridesLocalValue()
[xUnit.net 00:00:01.58]     ImplicitStyleDisabledVSMOverridesLocalValue [FAIL]
[xUnit.net 00:00:01.58]            at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
[xUnit.net 00:00:01.58]            at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  Passed GroupNamesMustBeUniqueWithinGroupList [< 1 ms]
  Skipped ValidatePerformance [1 ms]
  Passed InitialStateIsNullIfNormalNotAvailable [< 1 ms]
  Passed StateNamesMustBeUniqueWithinGroup [< 1 ms]
  Passed StateNamesMustBeUniqueWithinGroupList [< 1 ms]
  Passed VisualStateGroupsFromSettersAreDistinct [< 1 ms]
  Failed ImplicitStyleDisabledVSMOverridesLocalValue [12 ms]
  Error Message:
   Assert.Equal() Failure: Values differ
Expected: [Color: Red=0.5019608, Green=0.5019608, Blue=0.5019608, Alpha=1]
Actual:   [Color: Red=1, Green=0, Blue=0, Alpha=1]
  Stack Trace:
     at Microsoft.Maui.Controls.Core.UnitTests.VisualStateManagerTests.ImplicitStyleDisabledVSMOverridesLocalValue() in /_/src/Controls/tests/Core.UnitTests/VisualStateManagerTests.cs:line 594
   at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  Passed VisualElementGoesToCorrectStateWhenAvailable [< 1 ms]
  Passed StateNamesInGroupMayNotBeEmpty [< 1 ms]
[xUnit.net 00:00:01.59]   Finished:    Microsoft.Maui.Controls.Core.UnitTests
  Passed CanRemoveAStateAndAddANewStateWithTheSameName [< 1 ms]
  Passed VSMFromStyleAreUnApplied [5 ms]
  Passed UnapplyingVSMShouldUnapplySetters [< 1 ms]
  Passed StateNamesInGroupMayNotBeNull [< 1 ms]
  Passed VerifyVisualStateChanges [1 ms]
  Passed VisualElementGoesToCorrectStateWhenAvailableFromSetter [1 ms]

Test Run Failed.
Total tests: 24
     Passed: 22
     Failed: 1
    Skipped: 1
 Total time: 2.1582 Seconds

🟢 With fix — 🧪 VisualStateManagerTests: PASS ✅ · 79s

  Determining projects to restore...
  All projects are up-to-date for restore.
  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
  Graphics -> /home/vsts/work/1/s/artifacts/bin/Graphics/Debug/net10.0/Microsoft.Maui.Graphics.dll
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  Controls.Core -> /home/vsts/work/1/s/artifacts/bin/Controls.Core/Debug/net10.0/Microsoft.Maui.Controls.dll
  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
  Controls.Xaml -> /home/vsts/work/1/s/artifacts/bin/Controls.Xaml/Debug/net10.0/Microsoft.Maui.Controls.Xaml.dll
  ##vso[build.updatebuildnumber]10.0.60-ci+azdo.13736330
  Controls.Maps -> /home/vsts/work/1/s/artifacts/bin/Controls.Maps/Debug/net10.0/Microsoft.Maui.Controls.Maps.dll
  TestUtils -> /home/vsts/work/1/s/artifacts/bin/TestUtils/Debug/netstandard2.0/Microsoft.Maui.TestUtils.dll
  Controls.Core.UnitTests -> /home/vsts/work/1/s/artifacts/bin/Controls.Core.UnitTests/Debug/net10.0/Microsoft.Maui.Controls.Core.UnitTests.dll
Test run for /home/vsts/work/1/s/artifacts/bin/Controls.Core.UnitTests/Debug/net10.0/Microsoft.Maui.Controls.Core.UnitTests.dll (.NETCoreApp,Version=v10.0)
VSTest version 18.0.1 (x64)

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
[xUnit.net 00:00:00.00] xUnit.net VSTest Adapter v2.8.2+699d445a1a (64-bit .NET 10.0.0)
[xUnit.net 00:00:00.13]   Discovering: Microsoft.Maui.Controls.Core.UnitTests
[xUnit.net 00:00:01.27]   Discovered:  Microsoft.Maui.Controls.Core.UnitTests
[xUnit.net 00:00:01.28]   Starting:    Microsoft.Maui.Controls.Core.UnitTests
  Passed ElementsDoNotHaveVisualStateGroupsCollectionByDefault [10 ms]
  Passed StateNamesMustBeUniqueWithinGroupListWhenAddingGroup [2 ms]
  Passed VisualElementsStateGroupsAreDistinct [2 ms]
  Passed CustomImplicitStyleVSMStateDoesNotOverrideLocalValue [10 ms]
  Passed ChangingStyleContainingVSMShouldResetStateValue [3 ms]
  Passed AppThemeBindingInVSM [4 ms]
  Passed CanRemoveAGroupAndAddANewGroupWithTheSameName [< 1 ms]
  Passed InitialStateIsNormalIfAvailable [< 1 ms]
  Passed VisualElementGoesToCorrectStateWhenSetterHasTarget [4 ms]
[xUnit.net 00:00:01.40]     ValidatePerformance [SKIP]
[xUnit.net 00:00:01.40]       This test was created to check performance characteristics; leaving it in because it may be useful again.
  Passed GroupNamesMustBeUniqueWithinGroupList [< 1 ms]
  Skipped ValidatePerformance [1 ms]
  Passed InitialStateIsNullIfNormalNotAvailable [< 1 ms]
  Passed StateNamesMustBeUniqueWithinGroup [< 1 ms]
  Passed StateNamesMustBeUniqueWithinGroupList [< 1 ms]
  Passed VisualStateGroupsFromSettersAreDistinct [< 1 ms]
  Passed ImplicitStyleDisabledVSMOverridesLocalValue [5 ms]
  Passed VisualElementGoesToCorrectStateWhenAvailable [< 1 ms]
  Passed StateNamesInGroupMayNotBeEmpty [< 1 ms]
[xUnit.net 00:00:01.41]   Finished:    Microsoft.Maui.Controls.Core.UnitTests
  Passed CanRemoveAStateAndAddANewStateWithTheSameName [< 1 ms]
  Passed VSMFromStyleAreUnApplied [3 ms]
  Passed UnapplyingVSMShouldUnapplySetters [< 1 ms]
  Passed StateNamesInGroupMayNotBeNull [< 1 ms]
  Passed VerifyVisualStateChanges [< 1 ms]
  Passed VisualElementGoesToCorrectStateWhenAvailableFromSetter [< 1 ms]

Test Run Successful.
Total tests: 24
     Passed: 23
    Skipped: 1
 Total time: 1.9180 Seconds

📁 Fix files reverted (3 files)

• eng/pipelines/ci-copilot.yml
• src/Controls/src/Core/SetterSpecificity.cs
• src/Controls/src/Core/VisualStateManager.cs

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[MauiBot]

🤖 AI Summary

📊 Expand Full Review — 54499dc · Addressed copilot review concern

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🔍 Pre-Flight — Context & Validation

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Issue: #34363 - [regression/9.0] VisualState "Disabled" is not properly applied for Button with custom appearance
PR: #34444 - Fix Disabled visual state ignored when Button has locally-set BackgroundColor/TextColor
Platforms Affected: Android, iOS, macOS, Windows (regression since .NET MAUI 9.0)
Files Changed: 2 implementation, 1 test

Key Findings

• PR [regression/8.0.0] Button background does not override implicit visualstate style #18103 introduced a specificity downgrade for implicit-style VSM setters so the Normal state cannot override locally-set values. The downgrade inadvertently blocked ALL VSM states (not just Normal) from overriding locally-set values.
• Fix introduces WithFullVsmPriority() on SetterSpecificity that promotes an implicit VSM specificity to regular VSM priority.
• Fix adds IsSystemDrivenState() helper in VisualStateManager to enumerate MAUI framework-driven states: Disabled, Focused, Unfocused, Selected, PointerOver, Pressed.
• Only system-driven states get promoted; custom developer-defined states keep downgraded priority (preserves [regression/8.0.0] Button background does not override implicit visualstate style #18103 behavior for Normal state).
• Named bit-mask constants VsmMask / ImplicitVsmMask added to SetterSpecificity for maintainability (Copilot suggestion, addressed by author).
• Copilot raised concern about Pressed not being included in IsSystemDrivenState — addressed; it now includes ButtonElement.PressedVisualState.
• Test coverage: 2 new xUnit tests — ImplicitStyleDisabledVSMOverridesLocalValue and CustomImplicitStyleVSMStateDoesNotOverrideLocalValue.
• Test type: Unit tests (xUnit) in Controls.Core.UnitTests.csproj

Edge Cases / Review Concerns (from inline comments — all addressed)

• Pressed state missing from IsSystemDrivenState → now included
• Hard-coded bit masks in WithFullVsmPriority → replaced with named constants VsmMask / ImplicitVsmMask
• Comment referenced wrong issue number → fixed
• Test only asserted BackgroundColor, not TextColor → both properties now asserted

Fix Candidates

#	Source	Approach	Test Result	Files Changed	Notes
PR	PR #34444	Add WithFullVsmPriority() to SetterSpecificity; apply only for system-driven states in VSM GoToState	✅ PASSED (Gate)	SetterSpecificity.cs, VisualStateManager.cs	Original PR

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🔧 Fix — Analysis & Comparison

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Fix Candidates

#	Source	Approach	Test Result	Files Changed	Notes
1	claude-opus-4.6	Use existing VisualStateSetter constant for system-driven states — no SetterSpecificity changes	✅ PASS	VisualStateManager.cs only (1 file)	Simpler; may have subtle semantic diff vs CopyStyle
2	claude-sonnet-4.6	Add preserveVsmPriority bool param to CopyStyle — prevent implicit-VSM downgrade at source	✅ PASS	SetterSpecificity.cs, VisualStateManager.cs	Clean; 2 files like PR
3	gpt-5.3-codex	Use manual field as semantic marker (ManualTriggerBaseline); downgrade guard checks manual < baseline	✅ PASS	SetterSpecificity.cs, VisualStateManager.cs	Repurposes existing field in unintuitive way
4	gpt-5.4	VisualState.UsesFullVisualStatePriority property + CopyStyleForVisualState() factory	✅ PASS	SetterSpecificity.cs, VisualStateManager.cs	Clean abstraction but adds property to public model
5	gpt-5.4 (invert)	Downgrade ONLY Normal; all other states keep full VSM priority — required modifying PR's test to change expected behavior for custom states	✅ PASS*	VisualStateManager.cs	*Modified test to change semantics — incompatible with PR design intent
6	gpt-5.3-codex (stash)	Stash/clear local values for system-driven states on apply; restore on unapply	✅ PASS	VisualStateManager.cs	Bypasses specificity; invasive side-effects risk
PR	PR #34444	WithFullVsmPriority() bit-repair in SetterSpecificity; IsSystemDrivenState() allowlist; named constants	✅ PASSED (Gate)	SetterSpecificity.cs, VisualStateManager.cs	Original PR — explicit, maintainable, correct semantics

Cross-Pollination

Model	Round	New Ideas?	Details
claude-opus-4.6	2	No	NO NEW IDEAS — noted F avoids incomplete allowlist but doesn't flag semantic change
claude-sonnet-4.6	2	No	NO NEW IDEAS
gpt-5.3-codex	2	Yes	Stash/restore local values (→ attempt 6)
gpt-5.4	2	Yes	Invert rule — downgrade only Normal (→ attempt 5)
claude-opus-4.6	3	No	NO NEW IDEAS — declared solution space exhausted
gpt-5.3-codex	3	Yes*	"ImplicitVisualStateTransient tier" — variant of F+G combined; not materially different

Exhausted: Yes
Selected Fix: PR's fix — Reason: Approach F looks simpler but requires modifying the PR's explicit test CustomImplicitStyleVSMStateDoesNotOverrideLocalValue, changing the expected behavior so custom developer-defined states CAN override locally-set values — which is a broader semantic change beyond the bug fix. Approach B is technically simpler (1 file) but using VisualStateSetter constant directly has subtle semantic differences from a CopyStyle-derived specificity (different field values for binding/dynamicResource). The PR's fix (approach A) correctly targets system-driven states with an explicit allowlist, preserves the PR #18103 custom-state protection, uses clean named constants, and was thoroughly reviewed with all concerns addressed.

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📋 Report — Final Recommendation

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✅ Final Recommendation: APPROVE

Phase Status

Phase	Status	Notes
Pre-Flight	✅ COMPLETE	Issue #34363, 3 files changed (2 impl, 1 test)
Gate	✅ PASSED	Android — unit test ImplicitStyleDisabledVSMOverridesLocalValue FAIL→PASS
Try-Fix	✅ COMPLETE	6 attempts, all passing; PR's fix selected as best
Report	✅ COMPLETE

Summary

PR #34444 fixes a regression introduced in .NET MAUI 9.0 (PR #18103) where implicit-style VSM setters for system-driven states like Disabled and Focused could no longer override locally-set values (e.g., BackgroundColor, TextColor). The PR's fix correctly and surgically targets the problem with minimal changes, good test coverage, and clean code. All Copilot review concerns were addressed by the author. Multi-model exploration (6 independent approaches) failed to find a strictly better alternative — the PR's fix was selected as the best candidate.

Root Cause

PR #18103 introduced a specificity downgrade for implicit-style VSM setters: when an implicit style contains a VisualStateGroupsProperty setter, the resulting specificity has the IsVsmImplicit bit set, which causes it to lose to locally-set values. This was intended to protect the Normal state from overriding developer-set values. However, the downgrade applied indiscriminately to ALL states — Disabled, Focused, Unfocused, Selected, PointerOver, Pressed — meaning that even system-driven accessibility states like Disabled could not override locally-set property values.

Fix Quality

The PR's fix is well-constructed:

SetterSpecificity.cs

• Introduces named constants VsmMask and ImplicitVsmMask (replacing inline magic numbers in IsVsm/IsVsmImplicit) — improves maintainability
• Adds WithFullVsmPriority() with XML doc comment — promotes implicit VSM to full VSM by clearing the implicit bit and setting the regular VSM bit; guards with if (!IsVsmImplicit) return this to be a no-op for already-full specificities

VisualStateManager.cs

• IsSystemDrivenState() with XML doc comment enumerating the 6 system states: Disabled, Focused, Unfocused, Selected, PointerOver, ButtonElement.PressedVisualState
• Promotion applied consistently in both GoToState AND VisualStateGroupsPropertyChanged (both apply and unapply paths) — symmetry is important and correct
• Custom developer-defined states keep downgraded priority, preserving PR [regression/8.0.0] Button background does not override implicit visualstate style #18103 behavior

VisualStateManagerTests.cs

• ImplicitStyleDisabledVSMOverridesLocalValue — covers the exact regression scenario with both BackgroundColor and TextColor; verifies Normal-state non-override is preserved
• CustomImplicitStyleVSMStateDoesNotOverrideLocalValue — verifies the boundary condition that custom states remain downgraded

Remaining minor observation (non-blocking):
The IsSystemDrivenState allowlist does not include Checked/Unchecked/Indeterminate states used by CheckBox, Switch, or RadioButton. This could mean similar implicit-style VSM regressions exist for those controls. However, this is out of scope for this PR (which fixes the specifically reported Button/Disabled regression) and the test suite passes. A follow-up issue tracking the remaining states would be appropriate but is not a blocker for this PR.

Selected Fix: PR's fix

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