en-US

Block JavaScript optimizations on these sites

Supported on: Microsoft Edge version 134, Windows 7 or later

Registry

HKLM Software\Policies\Microsoft\Edge
HKCU Software\Policies\Microsoft\Edge

Options

List (registry values) list - list under Software\Policies\Microsoft\Edge\JavaScriptOptimizerBlockedForSites

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