Computer Configuration > Administrative Templates > Microsoft Edge > Performance
Both
HKLM\Software\Policies\Microsoft\Edge
This policy controls whether users can access the RAM (memory) resource control feature. This feature lets users set an individual limit on how much RAM (memory) the browser can use. To set a specific memory limit, use the 'TotalMemoryLimitMb' (Set limit on megabytes of memory a single Microsoft Edge instance can use) policy. If you enable or don't configure this policy, users can enable resource control and set the amount of RAM that Microsoft Edge can use. Browser performance may be affected by low limits. If you disable this policy, users can't use resource control.