autofirmer-expanded/scripts/install-extension-policy.ps1

<#
.SYNOPSIS
    Install the AutoFirmer extension from our own update server, via policy.

.DESCRIPTION
    Chrome will not side-load a CRX on Windows — dropping one on
    chrome://extensions is refused — and it will not update an unpacked folder.
    The supported way to run an extension you host yourself is a policy:
    ExtensionInstallForcelist names the extension id and the update manifest, and
    from then on the browser installs it, keeps it updated on its own schedule,
    and re-installs it if it goes missing.

    Edge and Brave are Chromium too: same CRX, same policy, same update
    manifest, only a different registry vendor key. By default this configures
    every one of the three that is actually installed.

    Defaults to the current user's policy hive, which needs no elevation.
    -Scope Machine writes to HKLM instead, for every account on the box; that
    one does need an elevated shell. Where both exist, HKLM wins.

    After this runs:
      * Remove the unpacked copy from chrome://extensions. It has the same id
        now, and the browser will not load both.
      * Restart the browser, or open chrome://policy and press "Reload policies".
      * A force-installed extension cannot be disabled or removed from the
        extensions page. Re-run with -Remove to take it off.

.EXAMPLE
    powershell -NoProfile -ExecutionPolicy Bypass -File scripts\install-extension-policy.ps1

.EXAMPLE
    powershell -NoProfile -ExecutionPolicy Bypass -File scripts\install-extension-policy.ps1 -Browser Edge -Scope Machine
#>
[CmdletBinding()]
param(
    [ValidateSet('All', 'Chrome', 'Edge', 'Brave')]
    [string]$Browser = 'All',

    [ValidateSet('User', 'Machine')]
    [string]$Scope = 'User',

    # Derived from the signing key on the droplet. It only changes if the key does.
    [string]$Id = 'lkjbblagjjbldlkeaaffhiopdlhniaan',

    [string]$UpdateUrl = 'https://ext.juicerroom.com/updates.xml',

    [switch]$Remove
)

$ErrorActionPreference = 'Stop'

# Vendor key under SOFTWARE\Policies, and the executable each one registers.
$vendors = @{
    Chrome = 'Google\Chrome'
    Edge   = 'Microsoft\Edge'
    Brave  = 'BraveSoftware\Brave'
}
$exes = @{
    Chrome = 'chrome.exe'
    Edge   = 'msedge.exe'
    Brave  = 'brave.exe'
}

function Test-BrowserInstalled([string]$Name) {
    # App Paths is where every one of these registers itself, per-machine or
    # per-user depending on how it was installed.
    foreach ($hive in @('HKLM:', 'HKCU:')) {
        if (Test-Path "$hive\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\$($exes[$Name])") {
            return $true
        }
    }
    return $false
}

$hive = if ($Scope -eq 'Machine') { 'HKLM:' } else { 'HKCU:' }

if ($Scope -eq 'Machine') {
    $identity = [Security.Principal.WindowsIdentity]::GetCurrent()
    if (-not ([Security.Principal.WindowsPrincipal]$identity).IsInRole(
            [Security.Principal.WindowsBuiltInRole]::Administrator)) {
        throw 'Run this from an elevated PowerShell for -Scope Machine, or drop the flag to install it for this user only.'
    }
}

$targets = if ($Browser -eq 'All') {
    @('Chrome', 'Edge', 'Brave') | Where-Object { Test-BrowserInstalled $_ }
} else {
    @($Browser)
}

if (-not $targets) {
    throw 'Found no Chrome, Edge or Brave installation. Name one with -Browser if it is installed somewhere unusual.'
}

$entry = "$Id;$UpdateUrl"

foreach ($target in $targets) {
    $key = "$hive\SOFTWARE\Policies\$($vendors[$target])\ExtensionInstallForcelist"

    if ($Remove) {
        if (-not (Test-Path $key)) {
            Write-Host "$target : nothing to remove — no $Scope forcelist."
            continue
        }
        $props = Get-ItemProperty $key
        $found = $false
        foreach ($name in ($props.PSObject.Properties.Name | Where-Object { $_ -notlike 'PS*' })) {
            if ($props.$name -like "$Id;*") {
                Remove-ItemProperty -Path $key -Name $name
                Write-Host "$target : removed entry $name ($($props.$name))"
                $found = $true
            }
        }
        if (-not $found) { Write-Host "$target : nothing to remove — $Id was not in the $Scope forcelist." }
        continue
    }

    if (-not (Test-Path $key)) { New-Item -Path $key -Force | Out-Null }

    # The forcelist is a list expressed as numbered values, so adding to it means
    # finding a free number rather than overwriting whatever is already there —
    # another extension may well be in the list.
    $props    = Get-ItemProperty $key
    $existing = $props.PSObject.Properties |
                Where-Object { $_.Name -notlike 'PS*' -and $_.Value -like "$Id;*" }

    if ($existing) {
        Set-ItemProperty -Path $key -Name $existing.Name -Value $entry
        Write-Host "$target : updated $Scope forcelist entry $($existing.Name)"
    } else {
        $used = $props.PSObject.Properties.Name |
                Where-Object { $_ -match '^\d+$' } | ForEach-Object { [int]$_ }
        $slot = if ($used) { (($used | Measure-Object -Maximum).Maximum + 1) } else { 1 }
        New-ItemProperty -Path $key -Name "$slot" -Value $entry -PropertyType String -Force | Out-Null
        Write-Host "$target : added $Scope forcelist entry $slot"
    }
    Write-Host "        $key"
}

if ($Remove) {
    Write-Host "`nRestart the browser to let the change take effect."
    exit 0
}

Write-Host @"

  $entry

Next:
  1. Remove the unpacked copy from chrome://extensions (same id — both cannot load).
  2. Restart the browser, or open its chrome://policy page and press "Reload policies".
  3. The card should read "Installed by enterprise policy".

From here the browser updates it on its own. The extension also asks for a check
as soon as the dashboard reports a newer version, so a release normally lands in
seconds rather than waiting out the browser's own cycle.
"@