Microsoft Edge
Controls whether the deprecated :--foo syntax for CSS custom state is enabled (obsolete)
Supported on Microsoft Edge version 127-132, Windows 7 or later
What it does
OBSOLETE: This policy is obsolete and doesn't work after Microsoft Edge 132. The :--foo syntax for the CSS custom state feature is being changed to :state(foo) in Microsoft Edge to comply with changes that are made in Firefox and Safari. This policy allows the deprecated syntax to be used until Stable 132. This deprecation breaks some Microsoft Edge-only websites that use the deprecated :--foo syntax. If you enable this policy, the deprecated syntax is enabled. If you disable or don't configure this policy, the deprecated syntax is disabled.
What it writes
- Hive
- HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
- Registry key
Software\Policies\Microsoft\Edge- Value name
CSSCustomStateDeprecatedSyntaxEnabled- When enabled
- DWORD 1
- When disabled
- DWORD 0
Configure and deploy
Choose a state; the output below is generated from the template for exactly that.
Enabled · Computer · template defaults
Registry file (.reg)
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge]
"CSSCustomStateDeprecatedSyntaxEnabled"=dword:00000001
PowerShell
$ErrorActionPreference = 'Stop'
function Set-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $PropertyType,
[Parameter(Mandatory = $true)][object] $Value
)
if (-not (Test-Path -LiteralPath $Path)) {
New-Item -Path $Path -Force | Out-Null
}
New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}
function Remove-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (Test-Path -LiteralPath $Path) {
Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
}
}
function Clear-RegistryKeyValues {
param(
[Parameter(Mandatory = $true)][string] $Path
)
if (-not (Test-Path -LiteralPath $Path)) {
return
}
foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
}
}
# Policy: Controls whether the deprecated :--foo syntax for CSS custom state is enabled (obsolete)
# Name: CSSCustomStateDeprecatedSyntaxEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx
Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'CSSCustomStateDeprecatedSyntaxEnabled' -PropertyType 'DWord' -Value 1
- The OMA-URI is an inferred ADMX-backed Policy CSP candidate derived from the source ADMX file name and policy name.
- Some Microsoft policies use built-in Policy CSP pages whose area names don't match the ADMX file name, so verify the candidate against Microsoft Learn before deployment.
ADMX profile candidate (OMA-URI)
./Device/Vendor/MSFT/Policy/Config/ADMX_msedge/CSSCustomStateDeprecatedSyntaxEnabledADMX SyncML candidate
<SyncML xmlns="SYNCML:SYNCML1.2">
<SyncBody>
<Replace>
<CmdID>1</CmdID>
<Item>
<Meta>
<Format>chr</Format>
<Type>text/plain</Type>
</Meta>
<Target>
<LocURI>./Device/Vendor/MSFT/Policy/Config/ADMX_msedge/CSSCustomStateDeprecatedSyntaxEnabled</LocURI>
</Target>
<Data><enabled/></Data>
</Item>
</Replace>
<Final/>
</SyncBody>
</SyncML>Intune remediation scripts
Detection
$ErrorActionPreference = 'Stop'
$reasons = [System.Collections.Generic.List[string]]::new()
function Test-RegistryValueExists {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (-not (Test-Path -LiteralPath $Path)) {
return $false
}
return $null -ne (Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue)
}
function Test-RegistryValueEquals {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $Kind,
[Parameter(Mandatory = $true)][object] $Expected
)
if (-not (Test-Path -LiteralPath $Path)) {
return $false
}
$valueObject = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue
if ($null -eq $valueObject) {
return $false
}
$actual = $valueObject.$Name
switch ($Kind) {
'String' { return [string]$actual -ceq [string]$Expected }
'ExpandString' { return [string]$actual -ceq [string]$Expected }
'DWord' { return [uint32]$actual -eq [uint32]$Expected }
'QWord' { return [uint64]$actual -eq [uint64]$Expected }
'MultiString' {
$actualArray = @($actual)
$expectedArray = @($Expected)
if ($actualArray.Count -ne $expectedArray.Count) { return $false }
for ($index = 0; $index -lt $actualArray.Count; $index++) {
if ([string]$actualArray[$index] -cne [string]$expectedArray[$index]) { return $false }
}
return $true
}
'Binary' {
$actualArray = [byte[]]$actual
$expectedArray = [byte[]]$Expected
if ($actualArray.Length -ne $expectedArray.Length) { return $false }
for ($index = 0; $index -lt $actualArray.Length; $index++) {
if ($actualArray[$index] -ne $expectedArray[$index]) { return $false }
}
return $true
}
default { return [string]$actual -ceq [string]$Expected }
}
}
# Policy: Controls whether the deprecated :--foo syntax for CSS custom state is enabled (obsolete)
# Name: CSSCustomStateDeprecatedSyntaxEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx
$isMatch = Test-RegistryValueEquals -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'CSSCustomStateDeprecatedSyntaxEnabled' -Kind 'DWord' -Expected 1
if (-not $isMatch) {
$reasons.Add('Value mismatch: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\CSSCustomStateDeprecatedSyntaxEnabled') | Out-Null
}
if ($reasons.Count -eq 0) {
Write-Output 'Compliant'
exit 0
}
$reasons | ForEach-Object { Write-Output $_ }
exit 1
Remediation
$ErrorActionPreference = 'Stop'
function Set-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name,
[Parameter(Mandatory = $true)][string] $PropertyType,
[Parameter(Mandatory = $true)][object] $Value
)
if (-not (Test-Path -LiteralPath $Path)) {
New-Item -Path $Path -Force | Out-Null
}
New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}
function Remove-RegistryValue {
param(
[Parameter(Mandatory = $true)][string] $Path,
[Parameter(Mandatory = $true)][string] $Name
)
if (Test-Path -LiteralPath $Path) {
Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
}
}
function Clear-RegistryKeyValues {
param(
[Parameter(Mandatory = $true)][string] $Path
)
if (-not (Test-Path -LiteralPath $Path)) {
return
}
foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
}
}
# Policy: Controls whether the deprecated :--foo syntax for CSS custom state is enabled (obsolete)
# Name: CSSCustomStateDeprecatedSyntaxEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx
Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'CSSCustomStateDeprecatedSyntaxEnabled' -PropertyType 'DWord' -Value 1
History 37 retained releases
- 150.0.4078.8016 Jul 2026
- Already present in the first release ChangeIntel keeps.
36 later releases left it unchanged.
Template
- Internal name
CSSCustomStateDeprecatedSyntaxEnabled- Namespace
Microsoft.Policies.Edge- Template file
msedge.admx- Release
- Microsoft Edge 155.0.4283.62 · file set
0a733b0040dbbf02…
Definition, editor controls and support
Definition
<policy class="Both" displayName="$(string.CSSCustomStateDeprecatedSyntaxEnabled)" explainText="$(string.CSSCustomStateDeprecatedSyntaxEnabled_Explain)" key="Software\Policies\Microsoft\Edge" name="CSSCustomStateDeprecatedSyntaxEnabled" presentation="$(presentation.CSSCustomStateDeprecatedSyntaxEnabled)" valueName="CSSCustomStateDeprecatedSyntaxEnabled" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
<parentCategory ref="Microsoft.Policies.Edge:microsoft_edge" />
<supportedOn ref="Microsoft.Policies.Edge:OBSOLETE_WIN7_V127_V132" />
<enabledValue>
<decimal value="1" />
</enabledValue>
<disabledValue>
<decimal value="0" />
</disabledValue>
</policy>Editor controls
<presentation id="CSSCustomStateDeprecatedSyntaxEnabled" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />Supported platforms and category
Microsoft.Policies.Edge:category:microsoft_edge
<category displayName="$(string.microsoft_edge)" name="microsoft_edge" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.Edge:definition:OBSOLETE_WIN7_V127_V132
<definition displayName="$(string.OBSOLETE_WIN7_V127_V132)" name="OBSOLETE_WIN7_V127_V132" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.Edge:category:microsoft_edge
<category displayName="$(string.microsoft_edge)" name="microsoft_edge" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.Edge:microsoft_edge">Microsoft Edge</string></strings>
Microsoft.Policies.Edge:definition:OBSOLETE_WIN7_V127_V132
<definition displayName="$(string.OBSOLETE_WIN7_V127_V132)" name="OBSOLETE_WIN7_V127_V132" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.Edge:OBSOLETE_WIN7_V127_V132">Microsoft Edge version 127-132, Windows 7 or later</string></strings>