Block JavaScript optimizations on these sites
Verified with Microsoft Edge 152.0.4191.53 — updated on July 10, 2026
Supported on: Microsoft Edge version 134, Windows 7 or later
Path in the GPO console
Computer Configuration\Administrative Templates\Microsoft Edge\Content settings User Configuration\Administrative Templates\Microsoft Edge\Content settings Description
Allows you to set a list of site url patterns that specify sites for which advanced JavaScript optimizations are disabled. Disabling JavaScript optimizations means that Microsoft Edge may render web content more slowly. For detailed information on valid url patterns, see https://go.microsoft.com/fwlink/?linkid=2095322. Wildcards, *, are allowed. JavaScript optimization policy exceptions will only be enforced at a site granularity (eTLD+1). A policy set for only subdomain.contoso.com won't correctly apply to contoso.com or subdomain.contoso.com since they both resolve to the same eTLD+1 (contoso.com) for which there's no policy. In this case, policy must be set on contoso.com to apply correctly for both contoso.com and subdomain.contoso.com. This policy applies on a frame-by-frame basis and isn't based on top-level origin url alone; so, for example, if contoso.com is listed in the 'JavaScriptOptimizerBlockedForSites' (Block JavaScript optimizations on these sites) policy but contoso.com loads a frame containing fabrikam.com, then contoso.com has JavaScript optimizations disabled, but fabrikam.com will use the policy from 'DefaultJavaScriptOptimizerSetting' (Control use of JavaScript optimizers), if set, or default to JavaScript optimizations enabled. Blocklist entries have higher priority than allowlist entries, which in turn have higher priority than the configured default value. If you don't configure this policy for a site, then the policy from 'DefaultJavaScriptOptimizerSetting' applies to the site, if set; otherwise, JavaScript optimization is enabled for the site. Example value: [*.]example.edu
Registry
Software\Policies\Microsoft\Edge Software\Policies\Microsoft\Edge Export Builder
BETAConfigure the state, scope and options, then generate .reg, PowerShell, Intune and SCCM outputs — or add the setting to a multi-setting collection.
These exports write the registry — this is not a managed GPO. ⓘ
Applying both scopes creates an ambiguous configuration (computer takes precedence over user). Only do this intentionally.
.reg file
Windows Registry Editor Version 5.00
; Exported from gporais.com
; Policy: Block JavaScript optimizations on these sites
; State: Enabled
; Scope: Computer (HKLM)
; Supported on: Microsoft Edge version 134, Windows 7 or later
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites]
; List values: enter one value per line in the builder UI.More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.Intune XML
No direct Policy CSP / OMA-URI mapping for this policy. Use the Intune Remediation tab, or ingest the ADMX in Intune.Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
# HKLM:\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites: List values: enter one value per line in the builder UI.
# No testable registry values are available for this state.
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.SCCM scripts
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
# SCCM Configuration Item guidance:
# Create a Configuration Item of type "Setting: Script".
# Discovery script: use the Detection script below.
# Remediation script: use the Remediation script below.
# Compliance rule: the Discovery script output equals 'Compliant'.
# === Detection script ===
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
# HKLM:\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites: List values: enter one value per line in the builder UI.
# No testable registry values are available for this state.
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Block JavaScript optimizations on these sites
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 134, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites'
New-Item -Path $path -Force | Out-Null
# List values: enter one value per line in the builder UI.Building a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.