@@ -2,4 +2,6 @@ src/UniGetUI.PackageEngine.Managers.Chocolatey/choco-cli/** linguist-vendored
 UniGetUI.iss whitespace=blank-at-eol,blank-at-eof,space-before-tab,cr-at-eol
 .githooks/* text eol=lf
 
-.github/workflows/*.lock.yml linguist-generated=true
+.github/workflows/*.lock.yml linguist-generated=true
+# Patches applied to other repositories must keep their line endings.
+.github/actions/desktop-session/ironrdp-patches/*.patch -text
@@ -102,4 +102,4 @@ remoting port and the desktop's Windows session id), `DESKTOP_SESSION_SIZE` and
 - UniGetUI's dialogs are drawn inside its main window, not as separate windows. UI Automation
   exposes the open dialog's title as the element with AutomationId `ModalTitle`. Escape closes it.
 - IronRDP is pinned through the `ironrdp-ref` input of `desktop-session`. Changing it rebuilds
-  and recaches `ironrdp-agent`, which takes about 5 minutes. A cache hit restores it in seconds.
+  and recaches `ironrdp-agent`, which takes about 9 minutes. A cache hit restores it in seconds.
@@ -239,6 +239,25 @@ function Invoke-DesktopCommand {
     Invoke-Command -Session (Get-DesktopPSSession) -ScriptBlock $ScriptBlock -ArgumentList $ArgumentList
 }
 
+# Runs a command in the desktop session over the NOW protocol: Devolutions Agent's RDP
+# extension runs it as the session's user, and its output comes back over the RDP virtual
+# channel. Needs the desktop-session action's now-channel input (DESKTOP_SESSION_NOW=1).
+# Throws when the command fails; returns its output.
+function Invoke-DesktopNowCommand {
+    param(
+        [Parameter(Mandatory)]
+        [string] $Command,
+
+        [ValidateSet('powershell', 'pwsh')]
+        [string] $Shell = 'powershell'
+    )
+
+    if ($env:DESKTOP_SESSION_NOW -ne '1') {
+        throw 'The NOW channel is not available in this desktop session (desktop-session now-channel input is off)'
+    }
+    Invoke-DesktopAgent now $Shell $Command
+}
+
 # Starts a program on the desktop and returns its process id and Windows session id.
 function Start-DesktopProcess {
     param(
@@ -419,6 +438,7 @@ Export-ModuleMember -Function @(
     'Get-DesktopPSSession',
     'Close-DesktopPSSession',
     'Invoke-DesktopCommand',
+    'Invoke-DesktopNowCommand',
     'Start-DesktopProcess',
     'Get-DesktopWindow',
     'Show-DesktopWindow'
 
@@ -16,7 +16,10 @@ param(
     [string] $DesktopSize = '1920x1080',
 
     [Parameter(Mandatory)]
-    [string] $ArtifactsDir
+    [string] $ArtifactsDir,
+
+    # Negotiate the NOW channel with Devolutions Agent's DevolutionsSession right after connecting.
+    [switch] $NowChannel
 )
 
 Set-StrictMode -Version Latest
@@ -160,6 +163,27 @@ try {
     $connected = $true
     Write-Host '::endgroup::'
 
+    if ($NowChannel) {
+        # DevolutionsSession, which Devolutions Agent starts once the session logs on, opens the
+        # Devolutions::Now::Agent channel and exits unless NOW negotiation starts within 5
+        # seconds. The daemon only negotiates on its first NOW request, which waits up to 30
+        # seconds for the channel, so that request is made right away. The daemon then keeps
+        # the negotiated channel alive.
+        Write-Host '::group::Negotiate NOW channel'
+        $capabilities = & $AgentPath --endpoint $endpoint now capabilities 2>&1 | Out-String
+        $capabilities | Set-Content -Path (Join-Path $ArtifactsDir 'now-capabilities.txt') -Encoding utf8NoBOM
+        Write-Host $capabilities.Trim()
+        if ($LASTEXITCODE -ne 0) {
+            throw "NOW negotiation with DevolutionsSession failed (exit code $LASTEXITCODE)"
+        }
+        # Tells later steps (and Invoke-DesktopNowCommand) that the NOW channel is up.
+        $env:DESKTOP_SESSION_NOW = '1'
+        if (-not [string]::IsNullOrWhiteSpace($env:GITHUB_ENV)) {
+            'DESKTOP_SESSION_NOW=1' | Add-Content -Path $env:GITHUB_ENV -Encoding utf8
+        }
+        Write-Host '::endgroup::'
+    }
+
     Write-Host '::group::Start interactive PSHostServer'
     Start-ScheduledTask -TaskName $taskName
     & (Join-Path $harnessRoot 'Start-InteractivePSHostServer.ps1') `
 
@@ -8,16 +8,27 @@ description: >
 inputs:
   ironrdp-ref:
     description: IronRDP commit providing ironrdp-agent and the testing/agentic-rdp harness
-    # IronRDP master at the merge of https://github.com/Devolutions/IronRDP/pull/2189, which
-    # hardened the harness. Pinned so the built agent can be cached by commit; changing it
-    # rebuilds ironrdp-agent once (about 5 minutes).
-    default: 75ee516f34562516bd400dbf6e2ef93de0521f22
+    # IronRDP master at the merge of https://github.com/Devolutions/IronRDP/pull/2209, which
+    # fixed the DVC pipe proxy for the NOW channel. Pinned so the built agent can be cached by
+    # commit; changing it rebuilds ironrdp-agent once (about 9 minutes).
+    default: 10199db3b0aeca629adc02234ffdbb570bb77d43
   desktop-size:
     description: RDP desktop size, as WxH
     default: 1920x1080
   artifacts-dir:
     description: Directory for screenshots, logs and session state; defaults to RUNNER_TEMP/desktop-session
     default: ''
+  devolutions-agent-version:
+    description: >
+      Version of the Devolutions.Agent winget package to install with its RDP extension, which
+      serves the NOW protocol over an RDP virtual channel in the desktop session; empty skips it
+    default: 2026.3.1.0
+  now-channel:
+    description: >
+      Negotiate the NOW channel with Devolutions Agent right after connecting, and check that a
+      command runs over it (Invoke-DesktopNowCommand). Needs an ironrdp-ref that includes
+      IronRDP#2209; before it, the first NOW message dropped the RDP session
+    default: 'false'
 
 outputs:
   agent-path:
@@ -47,7 +58,10 @@ runs:
   steps:
     # Cloned outside the workspace (actions/checkout can only write inside it), so the
     # caller's checkout stays clean for agents, git and tests that scan the repository.
+    # ironrdp-patches can hold fixes not yet merged in IronRDP, applied on top of ironrdp-ref
+    # (none at the moment).
     - name: Fetch IronRDP
+      id: fetch
       shell: pwsh
       env:
         IRONRDP_REF: ${{ inputs.ironrdp-ref }}
@@ -60,20 +74,29 @@ runs:
         git -C $env:IRONRDP_ROOT checkout --quiet --detach FETCH_HEAD
         if ($LASTEXITCODE -ne 0) { throw "git checkout failed with exit code $LASTEXITCODE" }
 
-    # The agent only changes with ironrdp-ref, so a cache hit skips the Rust build entirely.
+        $patches = @(Get-ChildItem -Path (Join-Path $env:GITHUB_ACTION_PATH 'ironrdp-patches') -Filter '*.patch' -File -ErrorAction SilentlyContinue | Sort-Object Name)
+        foreach ($patch in $patches) {
+          git -C $env:IRONRDP_ROOT apply $patch.FullName
+          if ($LASTEXITCODE -ne 0) { throw "Could not apply $($patch.Name) to IronRDP $env:IRONRDP_REF" }
+          Write-Host "Applied $($patch.Name)"
+        }
+        $patchHash = if ($patches.Count -gt 0) {
+          (($patches | Get-FileHash -Algorithm SHA256 | ForEach-Object Hash) -join '').Substring(0, 12)
+        } else { 'none' }
+        "patches=$patchHash" | Add-Content -Path $env:GITHUB_OUTPUT -Encoding utf8
+
+    # The agent only changes with ironrdp-ref and the patches, so a cache hit skips the Rust
+    # build entirely.
     - name: Restore ironrdp-agent
       id: agent-cache
       uses: actions/cache/restore@v6
       with:
         path: ${{ runner.temp }}/ironrdp/target/release/ironrdp-agent.exe
-        key: ironrdp-agent-${{ runner.os }}-${{ inputs.ironrdp-ref }}
-
-    - name: Rust cache
-      if: steps.agent-cache.outputs.cache-hit != 'true'
-      uses: Swatinem/rust-cache@v2.9.1
-      with:
-        workspaces: ${{ runner.temp }}/ironrdp
+        key: ironrdp-agent-${{ runner.os }}-${{ inputs.ironrdp-ref }}-${{ steps.fetch.outputs.patches }}
 
+    # No Rust build cache: it saved about 400 MB per branch, and the repository's 10 GB Actions
+    # cache then evicted this agent and the NuGet packages. A build from scratch is rare
+    # (a new ironrdp-ref, or an evicted agent) and takes about 9 minutes.
     - name: Build ironrdp-agent
       if: steps.agent-cache.outputs.cache-hit != 'true'
       shell: pwsh
@@ -97,13 +120,85 @@ runs:
         path: ${{ runner.temp }}/ironrdp/target/release/ironrdp-agent.exe
         key: ${{ steps.agent-cache.outputs.cache-primary-key }}
 
+    # The harness drives the interactive desktop through AwakeCoding.PSRemoting, and installs
+    # it with Install-Module when it is missing. ModuleFast installs it in about half the time,
+    # into the same CurrentUser folder, so the harness finds it and skips its own install.
+    - name: Install PowerShell modules
+      shell: pwsh
+      env:
+        MODULEFAST_RELEASE: v0.6.1
+        MODULES: AwakeCoding.PSRemoting=2026.10.21
+      run: |
+        # Created up front: ModuleFast asks before creating a destination folder.
+        $destination = Join-Path ([Environment]::GetFolderPath('MyDocuments')) 'PowerShell\Modules'
+        New-Item -Path $destination -ItemType Directory -Force | Out-Null
+        $bootstrap = Invoke-RestMethod "https://github.com/JustinGrote/ModuleFast/releases/download/$env:MODULEFAST_RELEASE/ModuleFast.ps1"
+        & ([scriptblock]::Create($bootstrap)) -Release $env:MODULEFAST_RELEASE `
+          -Specification ($env:MODULES -split ',') `
+          -Destination $destination `
+          -NoPSModulePathUpdate `
+          -NoProfileUpdate
+
+    # Devolutions Agent with its RDP extension (the F.Session feature, which sets Session.Enabled
+    # in agent.json): the agent starts DevolutionsSession in each RDP session, and it serves the
+    # NOW protocol over a virtual channel for remote execution. The agent only does that when an
+    # RDP session connects, so it is installed before the desktop session is. winget is not on
+    # the runner image, so the MSI comes from the package's winget manifest, checked against the
+    # manifest's hash.
+    - name: Install Devolutions Agent
+      if: inputs.devolutions-agent-version != ''
+      shell: pwsh
+      env:
+        AGENT_VERSION: ${{ inputs.devolutions-agent-version }}
+        ARTIFACTS_DIR: ${{ inputs.artifacts-dir }}
+      run: |
+        $artifactsDir = $env:ARTIFACTS_DIR
+        if ([string]::IsNullOrWhiteSpace($artifactsDir)) {
+          $artifactsDir = Join-Path $env:RUNNER_TEMP 'desktop-session'
+        }
+        New-Item -Path $artifactsDir -ItemType Directory -Force | Out-Null
+
+        $manifestUrl = "https://raw.githubusercontent.com/microsoft/winget-pkgs/master/manifests/d/Devolutions/Agent/$env:AGENT_VERSION/Devolutions.Agent.installer.yaml"
+        $manifest = Invoke-RestMethod -Uri $manifestUrl
+        $installer = [regex]::Match($manifest, '(?m)^- Architecture: x64\s*\r?\n\s+InstallerUrl: (?<url>\S+)\s*\r?\n\s+InstallerSha256: (?<sha>[0-9A-Fa-f]{64})')
+        if (-not $installer.Success) {
+          throw "No x64 installer in $manifestUrl"
+        }
+
+        $msiPath = Join-Path $env:RUNNER_TEMP 'DevolutionsAgent.msi'
+        Invoke-WebRequest -Uri $installer.Groups['url'].Value -OutFile $msiPath
+        $hash = (Get-FileHash -Path $msiPath -Algorithm SHA256).Hash
+        if ($hash -ne $installer.Groups['sha'].Value.ToUpperInvariant()) {
+          throw "$($installer.Groups['url'].Value) has SHA256 $hash, but the winget manifest expects $($installer.Groups['sha'].Value)"
+        }
+
+        $logPath = Join-Path $artifactsDir 'devolutions-agent-install.log'
+        $msiexec = Start-Process -FilePath 'msiexec.exe' -Wait -PassThru -ArgumentList @(
+          '/i', "`"$msiPath`"", '/qn', '/norestart', 'ADDLOCAL=F.Agent,F.Session', '/l*v', "`"$logPath`""
+        )
+        if ($msiexec.ExitCode -notin 0, 3010) {
+          throw "Devolutions Agent setup failed with exit code $($msiexec.ExitCode); log in $logPath"
+        }
+
+        $configPath = Join-Path $env:ProgramData 'Devolutions\Agent\agent.json'
+        $config = Get-Content -Path $configPath -Raw | ConvertFrom-Json
+        if (-not ($config.PSObject.Properties['Session'] -and $config.Session.Enabled)) {
+          throw "Session.Enabled is not set in $configPath after installing the RDP extension"
+        }
+        $service = Get-Service -Name 'DevolutionsAgent'
+        if ($service.Status -ne 'Running') {
+          Start-Service -Name 'DevolutionsAgent'
+        }
+        Write-Host "Devolutions Agent $env:AGENT_VERSION installed with its RDP extension; service $((Get-Service -Name 'DevolutionsAgent').Status)"
+
     - name: Start desktop session
       id: start
       shell: pwsh
       env:
         IRONRDP_ROOT: ${{ runner.temp }}/ironrdp
         DESKTOP_SIZE: ${{ inputs.desktop-size }}
         ARTIFACTS_DIR: ${{ inputs.artifacts-dir }}
+        NOW_CHANNEL: ${{ inputs.devolutions-agent-version != '' && inputs.now-channel == 'true' }}
       run: |
         $artifactsDir = $env:ARTIFACTS_DIR
         if ([string]::IsNullOrWhiteSpace($artifactsDir)) {
@@ -113,4 +208,49 @@ runs:
         & "$env:GITHUB_ACTION_PATH\Start-DesktopSession.ps1" `
           -IronRdpRoot $env:IRONRDP_ROOT `
           -DesktopSize $env:DESKTOP_SIZE `
-          -ArtifactsDir $artifactsDir
+          -ArtifactsDir $artifactsDir `
+          -NowChannel:($env:NOW_CHANNEL -eq 'true')
+
+    # Checks the RDP extension end to end: DevolutionsSession runs in the desktop session, and a
+    # command sent over the NOW channel runs there. The command is retried, since it sometimes
+    # fails with "NOW operation stream closed before a terminal event" right after the
+    # handshake. If NOW still doesn't work, later steps go without it (DESKTOP_SESSION_NOW=0)
+    # rather than the whole job failing.
+    - name: Check NOW remote execution
+      if: inputs.devolutions-agent-version != '' && inputs.now-channel == 'true'
+      shell: pwsh
+      env:
+        SESSION_ID: ${{ steps.start.outputs.session-id }}
+      run: |
+        $sessionId = [int] $env:SESSION_ID
+
+        # The agent's and DevolutionsSession's logs go with the desktop session artifacts either way.
+        $agentLogs = Join-Path $env:DESKTOP_SESSION_ARTIFACTS 'devolutions-agent'
+        New-Item -Path $agentLogs -ItemType Directory -Force | Out-Null
+        Get-ChildItem -Path (Join-Path $env:ProgramData 'Devolutions\Agent') -File -Filter 'agent*' |
+          Copy-Item -Destination $agentLogs
+        Get-ChildItem -Path (Join-Path $env:APPDATA 'Devolutions\Session') -File -ErrorAction SilentlyContinue |
+          Copy-Item -Destination $agentLogs
+
+        $process = Get-Process -Name 'DevolutionsSession' -ErrorAction SilentlyContinue |
+          Where-Object { $_.SessionId -eq $sessionId } |
+          Select-Object -First 1
+        $failure = if ($null -eq $process) { "DevolutionsSession is not running in desktop session $sessionId" } else { $null }
+
+        # The remote command prints the session it runs in, which must be the desktop session.
+        for ($attempt = 1; $null -ne $process -and $attempt -le 3; $attempt++) {
+          $output = & $env:DESKTOP_SESSION_AGENT --endpoint $env:DESKTOP_SESSION_ENDPOINT now powershell '(Get-Process -Id $PID).SessionId' 2>&1 | Out-String
+          if ($LASTEXITCODE -eq 0 -and $output -match "(?m)^\s*$sessionId\s*$") {
+            $failure = $null
+            Write-Host "DevolutionsSession (pid $($process.Id)) ran a PowerShell command in desktop session $sessionId over NOW (attempt $attempt)"
+            break
+          }
+          $failure = "NOW remote execution in desktop session $sessionId failed (exit code $LASTEXITCODE): $($output.Trim())"
+          Write-Host "Attempt ${attempt}: $failure"
+          Start-Sleep -Seconds 5
+        }
+
+        if ($failure) {
+          Write-Host "::warning::$failure. The desktop session continues without NOW; logs in $agentLogs"
+          'DESKTOP_SESSION_NOW=0' | Add-Content -Path $env:GITHUB_ENV -Encoding utf8
+        }
@@ -40,8 +40,9 @@ runs:
     - name: Build UniGetUI installer
       id: build
       shell: pwsh
+      # NuGet's cache folders (NUGET_PACKAGES, NUGET_HTTP_CACHE_PATH) come from the calling
+      # workflow's env.
       env:
-        NUGET_PACKAGES: ${{ github.workspace }}/.nuget/packages
         OUTPUT_DIR: ${{ inputs.output-dir }}
         # MSBuild reads environment variables as properties. As in build-release.yml, build
         # project references one at a time without the shared compiler server: parallel