Regression: ExtensionSettings installation_mode: normal_installed toggle becomes non-interactive/locked starting Edge 151+ (works correctly on 150.0.4078.105 and earlier)

Issue

We manage a Chromium extension deployed to enterprise devices via the ExtensionSettings policy with:

"installation_mode": "normal_installed"

The intended behavior is to allow end users to manually enable or disable the extension from edge://extensions on demand.

Expected Behavior

With installation_mode: normal_installed, the extension's enable/disable toggle on edge://extensions should remain interactive, allowing users to turn the extension on or off.

Observed Behavior

Starting with Edge 151, the toggle renders locked/greyed out and becomes non-interactive for the same extension IDs under the identical ExtensionSettings policy.

The extension also appears disabled in the UI, rather than simply having a non-toggleable control.

This is unexpected because normal_installed is not documented as a policy-managed/locked installation mode.

Side-by-Side Comparison

We confirmed the behavior by comparing the edge://policy JSON exports from both machines. The ExtensionSettings configuration is identical; the only relevant difference is the Edge version.

  | Working Machine | Broken Machine -- | -- | -- Edge version | 150.0.4078.144 (Official build, 64-bit) | 152.0.4191.53+ (Official build, 64-bit) installation_mode | normal_installed | normal_installed (identical) Toggle behavior | Interactive; user can enable/disable | Locked, greyed out, non-interactive

Chrome Comparison

The same extension and the same policy configuration work correctly in Chrome at an equivalent version.

This suggests the behavior may be specific to Edge rather than a general Chromium policy change.

Reproduction Policy

The relevant machine-scope ExtensionSettings configuration is:

{
  "<extension-id>": {
    "installation_mode": "normal_installed",
    "update_url": "https://.../update.xml"
  }
}

Additional Policy Information

The edge://policy export also shows the following warning:

More than one source with conflicting values is present for this policy!

This is caused by a separate user-scope ExtensionSettings policy from a third-party security tool.

We have confirmed that this policy conflict is present identically on both the working and broken machines, so it does not appear to be the cause of the issue.

However, we are flagging it in case it is relevant to Edge's internal policy-merging or policy-resolution logic and could interact with the observed behavior.

Impact

Enterprise customers relying on normal_installed for user-togglable managed extensions lose the ability to enable or disable the extension after upgrading beyond Edge 150.0.4078.105.

No policy-side workaround has been identified so far.

Request

Please confirm:

1. Whether this behavior is an intentional policy-enforcement change introduced in Edge 151+, or a regression.

2. If intentional, what is the correct ExtensionSettings policy configuration to preserve user enable/disable capability for managed extensions in Edge 151+?

3. If this is a regression, whether there is a known fix or workaround available.