JavaScriptOptimizerBlockedForSites

Block JavaScript optimizations on these sites

Supported versions

• On Windows and macOS since 134 or later
• On Android since 138 or later

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 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, 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.

Supported features

• Can be mandatory: Yes
• Can be recommended: No
• Dynamic Policy Refresh: Yes
• Per Profile: Yes
• Applies to a profile that is signed in with a Microsoft account: No

Data type

• List of strings

Windows information and settings

Group Policy (ADMX) info

• GP unique name: JavaScriptOptimizerBlockedForSites
• GP name: Block JavaScript optimizations on these sites
• GP path (Mandatory): Administrative Templates/Microsoft Edge/Content settings
• GP path (Recommended): N/A
• GP ADMX file name: MSEdge.admx

Example value

[*.]example.edu

Registry settings

• Path (Mandatory): SOFTWARE\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites
• Path (Recommended): N/A
• Value name: 1, 2, 3, ...
• Value type: List of REG_SZ

Example registry value

SOFTWARE\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites\1 =

[*.]example.edu

Mac information and settings

• Preference Key name: JavaScriptOptimizerBlockedForSites
• Example value:

<array>
  <string>[*.]example.edu</string>
</array>

Android information and settings

• Preference Key name: JavaScriptOptimizerBlockedForSites
• Example value:

["[*.]example.edu"]

See also

• Microsoft Edge - Policies