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GeezerVison is showing github.com — Fix -WindowStyle Hidden console window flash by SufficientDaikon · Pull Request #27111 · PowerShell/PowerShell

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Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

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PR Summary

Eliminate the console window flash when launching pwsh -WindowStyle Hidden on Windows 11 24H2+ by using the consoleAllocationPolicy=detached manifest element and AllocConsoleWithOptions kernel32 API.

Fixes #3028

Important

Progressive enhancement: On older Windows the manifest is ignored and behavior is identical to the current release. On newer Windows (build 26100+) the console window is never created in the first place.

On Windows 11 build 26100+, the OS no longer auto-creates a console window for pwsh.exe — PowerShell allocates it programmatically at the top of Main():

-WindowStyle Hidden — AllocConsoleWithOptions(NoWindow): console I/O works, no window appears
Normal launch — AllocConsoleWithOptions(Default): respects DETACHED_PROCESS from the parent (per DHowett's review)
Older Windows — API not available → TryAlloc* returns false via catch (EntryPointNotFoundException) → no-op (OS already auto-allocated the console)

No AllocConsole() fallback in EarlyConsoleInit — plain AllocConsole() would override DETACHED_PROCESS from the parent. On older Windows the manifest is ignored, so the OS auto-allocates the console before Main() runs and GetConsoleWindow() returns non-zero — EarlyConsoleInit is a no-op.

pwsh.exe stays a CUI subsystem binary. No new executables, no breaking changes, no new public API.

Changes

File	Change
`assets/pwsh.manifest`	Add `consoleAllocationPolicy=detached` in a new `<application>` block (asm.v3 xmlns required)
`engine/Interop/Windows/AllocConsoleWithOptions.cs`	New — P/Invoke for `AllocConsoleWithOptions`, shared `TryAllocConsoleWithMode()` helper, checks `AllocConsoleResult != NoConsole`
`host/msh/ManagedEntrance.cs`	New `EarlyConsoleInit(args)` + `EarlyCheckForHiddenWindowStyle(args)`
`host/msh/ConsoleControl.cs`	`SetConsoleMode()` guards against null handle — graceful return instead of `Dbg.Assert`
`engine/NativeCommandProcessor.cs`	`AllocateHiddenConsole()` prefers `AllocConsoleWithOptions(NoWindow)` with `AllocConsole()` fallback (native commands always need a console)
`test/powershell/Host/WindowStyleHidden.Tests.ps1`	New — 13 Pester tests (Pester 4 compatible)

Behavior by launch context

Context	Old Windows	Windows 26100+
Terminal / cmd / pwsh	Console inherited — unchanged	Console inherited — unchanged
Explorer double-click	OS creates console — unchanged	`AllocConsoleWithOptions(Default)`
`CreateProcess(DETACHED_PROCESS)`	No console — unchanged	`Default` mode respects detached intent
`CreateProcess(CREATE_NO_WINDOW)`	Console session, no window — unchanged	`AllocConsoleWithOptions` returns `ExistingConsole` (no-op)
`DETACHED_PROCESS` + `-WindowStyle Hidden`	No console (crash)	`NoWindow` creates invisible console — user explicitly requested working I/O
Task Scheduler + `-WindowStyle Hidden`	Flash then hide	No flash
Shortcut + `-WindowStyle Hidden`	Flash then hide	No flash

  public static int Start(string[] args, int argc)
  {
      ArgumentNullException.ThrowIfNull(args);
+
+ #if !UNIX
+     // Allocate console before anything touches CONOUT$/CONIN$ handles.
+     EarlyConsoleInit(args);
+ #endif
+
  #if DEBUG

Warning

Ordering constraint: EarlyConsoleInit() must run before EarlyStartup.Init(). The Lazy<ConsoleHandle> in ConsoleControl.cs opens CONOUT$ via CreateFile — it's a once-only Lazy initializer, so if accessed before a console exists, the HostException is cached permanently. The console must exist before any background warmup (AMSI, Compiler init) touches it.

Root cause and how the fix works

flowchart TD
    A["pwsh.exe launched with\n-WindowStyle Hidden"] --> B{"Windows checks\nPE subsystem"}

    B -->|"CUI (current behavior)"| C["OS creates visible\nconsole window"]
    C --> D["Main() starts"]
    D --> E["PowerShell parses\n-WindowStyle Hidden"]
    E --> F["ShowWindow(SW_HIDE)"]
    F --> G["Window already\nflashed on screen"]

    B -->|"CUI + detached manifest\n(this PR)"| H["OS skips\nconsole allocation"]
    H --> I["Main() starts"]
    I --> J["EarlyConsoleInit()\nscans args immediately"]
    J --> K["AllocConsoleWithOptions\n(NoWindow)"]
    K --> L["Console I/O works\nNo window ever appeared"]

The key insight: previous fixes tried to hide the window faster. This fix prevents the window from being created at all by shifting console allocation from the OS to PowerShell.

How `EarlyConsoleInit` decides what to do

flowchart LR
    A["EarlyConsoleInit(args)"] --> B{"GetConsoleWindow()\n!= 0?"}
    B -->|"Yes (inherited /\nolder Windows)"| C["return\n(leave to SetConsoleMode)"]

    B -->|"No (detached policy /\nDETACHED_PROCESS /\nCREATE_NO_WINDOW)"| F{"-WindowStyle\nHidden?"}
    F -->|Yes| G["TryAllocConsoleNoWindow()"]
    F -->|No| H["TryAllocConsoleDefault()"]

    G -->|"API missing\n(older Windows)"| I["no-op\n(preserve existing behavior)"]
    H -->|"API missing\n(older Windows)"| J["no-op\n(preserve existing behavior)"]

Early arg scan design

EarlyCheckForHiddenWindowStyle(args) runs before CommandLineParameterParser. Uses ReadOnlySpan<char> for zero heap allocations.

Matches:

Single dash: -w, -wi, -win, ..., -windowstyle
Double dash: --w, --windowstyle (strips second dash, matching GetSwitchKey)
Forward slash: /w, /windowstyle
Case-insensitive via StringComparison.OrdinalIgnoreCase

Design tradeoffs:

False positives acceptable — worst case is allocating a hidden console that the full parser later makes visible
False negatives fall through to the existing SetConsoleMode path which handles -WindowStyle via ShowWindow
Colon syntax (-windowstyle:hidden) intentionally unhandled — the full parser's MatchSwitch also does not split on colons for this parameter

Why no AllocConsole() fallback in EarlyConsoleInit

Per DHowett's review: plain AllocConsole() overrides DETACHED_PROCESS from the parent's CreateProcess call and force-creates a console. AllocConsoleWithOptions with Default mode respects the parent's intent.

The manifest (consoleAllocationPolicy=detached) and the API (AllocConsoleWithOptions) were designed and shipped together in Windows 11 build 26100. Therefore:

API available → manifest is effective → TryAlloc* handles everything
API not available → manifest is ignored → OS auto-allocated the console → GetConsoleWindow() != 0 → EarlyConsoleInit returns early (no-op)
DETACHED_PROCESS on older Windows → only path where TryAlloc* returns false and no console exists → existing behavior is no console I/O; a plain AllocConsole() fallback would defeat DETACHED_PROCESS

NativeCommandProcessor.AllocateHiddenConsole() retains its AllocConsole() fallback because native commands unconditionally need a console for I/O — that's a different contract than startup allocation.

Both TryAllocConsoleNoWindow() and TryAllocConsoleDefault() funnel through a shared TryAllocConsoleWithMode() helper that checks result != AllocConsoleResult.NoConsole.

DETACHED_PROCESS + -WindowStyle Hidden

daxian-dbw raised an inconsistency: with -WindowStyle Hidden, NoWindow mode creates a console even under DETACHED_PROCESS, while without -WindowStyle Hidden, Default mode respects DETACHED_PROCESS and creates none.

This is intentional. Per the API docs, ALLOC_CONSOLE_MODE_NO_WINDOW "allocates a console session without a window, even if this process was created with DETACHED_PROCESS." When the user explicitly passes -WindowStyle Hidden, they are requesting invisible PowerShell with working I/O (Write-Host, native commands, pipeline). The alternative — honoring DETACHED_PROCESS and providing no console, causing stdin/stdout crashes — is strictly worse.

Launch flags	Without `-WindowStyle Hidden`	With `-WindowStyle Hidden`
Normal	`Default` → new visible console	`NoWindow` → new invisible console
`DETACHED_PROCESS`	`Default` → `NoConsole` (respected)	`NoWindow` → new invisible console (user asked for I/O)
`CREATE_NO_WINDOW`	`Default` → `ExistingConsole` (no-op)	`NoWindow` → `ExistingConsole` (no-op)

API reference

API	Docs	Notes
`AllocConsoleWithOptions`	learn.microsoft.com	Returns `HRESULT`, takes `ALLOC_CONSOLE_OPTIONS` and `ALLOC_CONSOLE_RESULT`
`ALLOC_CONSOLE_OPTIONS`	learn.microsoft.com	`{ ALLOC_CONSOLE_MODE mode; BOOL useShowWindow; WORD showWindow; }`

Minimum: Windows 11 24H2 (build 26100) / Windows Server 2025

Test coverage

13 Pester tests in WindowStyleHidden.Tests.ps1 (Pester 4 compatible — -Skip on It blocks, not Context):

Context	Tests
Manifest verification	PE embedded manifest extraction
Output capture	`-WindowStyle Hidden -Command`, pipeline, `Write-Host`, exit codes
Arg prefix variants	`-w`, `-win`, `--windowstyle`, `/windowstyle`, `-WINDOWSTYLE`
API probe	`AllocConsoleWithOptions` availability detection
Regression	Normal startup, `-WindowStyle Normal`

Known limitations

Unix: All changes are #if !UNIX guarded — no effect, no risk.
Windows Server Core / RDP sessions: Not explicitly tested. Progressive enhancement design means no regression risk, but behavior under headless or remote display contexts has not been verified.
-NonInteractive interaction: The early arg scan only looks for -WindowStyle Hidden. It does not check -NonInteractive. This matches existing behavior (the full parser handles -NonInteractive separately).
pwsh-preview.exe: No separate pwsh-preview.manifest exists in the repo. If the preview binary shares the same manifest, the fix applies automatically.
Colon syntax (-windowstyle:hidden): Intentionally unhandled — the full parser's MatchSwitch also does not split on colons for this parameter. Open to guidance if reviewers feel the early scan should handle it.

PR Context

Issue #3028 has been open since January 2017 with 160+ upvotes. Two previous PRs attempted to fix it:

PR	Approach	Result
#10962	Separate `pwshw.exe` (WinExe subsystem)	Closed — 127 test failures; `Write-Host`, `Read-Host`, native commands broke
#10965	Parser-level changes	Closed — 66 test failures

Both failed because pwsh.exe is a CUI binary and Windows creates a visible console window before Main() runs. The flash cannot be eliminated by optimizing managed code startup — the window is created by the Windows loader. The fix required an OS-level mechanism: consoleAllocationPolicy and AllocConsoleWithOptions, shipped in Windows 11 build 26100. The Windows Console team (DHowett — designer/implementer of consoleAllocationPolicy) recommended this approach in issue #3028.

📚 Interactive walkthrough of this fix — visual before/after comparisons, annotated source changes, and quizzes

PR Checklist

PR has a meaningful title
- Use the present tense and imperative mood when describing your changes
Summarized changes
Make sure all .h, .cpp, .cs, .ps1 and .psm1 files have the correct copyright header
This PR is ready to merge. If this PR is a work in progress, please open this as a Draft Pull Request and mark it as Ready to Review when it is ready to merge.
Breaking changes
- None
- OR
- Experimental feature(s) needed
  - Experimental feature name(s):
User-facing changes
- Not Applicable
- OR
- Documentation needed
  - Issue filed: Document -WindowStyle Hidden behavior change on Windows 11 24H2+ MicrosoftDocs/PowerShell-Docs#12897
Testing - New and feature
- N/A or can only be tested interactively
- OR
- Make sure you've added a new test if existing tests do not effectively test the code changed

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          Fix -WindowStyle Hidden console window flash

5dfe5ae

Use consoleAllocationPolicy=detached manifest and AllocConsoleWithOptions
to prevent the OS from auto-allocating a visible console window on newer
Windows. On older Windows the manifest is ignored and behavior is unchanged.

On Windows 11 build 26100+, the detached policy stops the OS from
creating a console window before any code runs. PowerShell now allocates
the console itself at the earliest point in startup — visibly for
interactive use, or invisibly via AllocConsoleWithOptions(NoWindow) when
-WindowStyle Hidden is specified.

This approach was recommended by @DHowett (Windows Console team) in
PowerShell#3028 (comment)

Fix PowerShell#3028

Ahmed Taha (SufficientDaikon) requested a review from a team as a code owner

March 28, 2026 12:42


          Address review: zero-alloc arg scan, shared helper, test cleanup

4b4a8ef

- Replace Substring(1) with AsSpan(1) for zero-alloc early arg parsing
- Extract TryAllocConsoleNoWindow() into Interop.Windows (DRY)
- Add XML doc comments to AllocConsoleWithOptions enums and struct
- Document colon-syntax and false-positive behavior in arg scanner
- Change test tag from CI to Feature (matches existing WindowStyle tests)
- Remove hardcoded build number from API probe test
- Add -ErrorAction Stop to Add-Type in tests
- Use double quotes consistently in test file

Dustin L. Howett (DHowett) commented Mar 28, 2026

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This sounds awesome! I haven't been able to give it an in-depth review, but I do have a note from reading the PR description.

If you are on a version of Windows which has AllocConsoleWithOptions, you should always use it (when coupled with the "detached" policy). Using AllocConsole will override a CreateProcess(... DETACHED_PROCESS), whereas AllocConsoleWithOptions with ALLOC_CONSOLE_MODE_DEFAULT will respect DETACHED_PROCESS.

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          Use AllocConsoleWithOptions(Default) for normal launches

1a86fe6

Per DHowett's feedback: plain AllocConsole() overrides DETACHED_PROCESS
from the parent's CreateProcess call. AllocConsoleWithOptions with
Default mode respects it. Extract shared TryAllocConsoleWithMode() and
add TryAllocConsoleDefault() alongside TryAllocConsoleNoWindow().

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

edited

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Thanks Dustin L. Howett (@DHowett)! Great catch — you're absolutely right.

I've pushed a fix in 1a86fe6: normal (non-hidden) launches now use AllocConsoleWithOptions(Default) instead of plain AllocConsole(), so DETACHED_PROCESS from the parent's CreateProcess call is properly respected.

The logic is now:

-WindowStyle Hidden → AllocConsoleWithOptions(NoWindow) — invisible console session
Normal launch → AllocConsoleWithOptions(Default) — respects parent's detach intent
Older Windows (API missing) → falls back to AllocConsole() via catch (EntryPointNotFoundException)

Both helpers go through a shared TryAllocConsoleWithMode() to keep it DRY.

generated by opus.

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Dustin L. Howett (DHowett) commented Mar 28, 2026

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Great catch — you're absolutely right.

It is rude to respond to people with AI-generated text.

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          Merge branch 'master' into fix/windowstyle-hidden-console-flash

b2a7b30

Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

edited

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Dustin L. Howett (@DHowett) i'm sorry, won't happen again.

i automated the process too much, i'm working on dialing it down and adding rules to prevent comments all together because that's not at all the kind of automation i'm looking for.

but yes, thank you so much for your reply, and i really do appreciate it because the powershell repo is waaay to big for me to understand quickly enough for my PRs to not have mistakes, so i need feedback so i can keep working on iterating on the PRs i'm making quickly so they get merged as cleanly as easily as possible.

again, i apologize, that is incrediblly rude, i didn't mean for that to happen at all, i also acknowledge that i should've been more attentive of what my powershell agent was doing.

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Dustin L. Howett (DHowett) commented Mar 28, 2026

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Ahmed Taha (@SufficientDaikon) hey thanks for saying all that :) it's really cool that the tools of the modern day allow you to take on a daunting task like this! I know everyone's still figuring out their whole workflow, so don't feel too bad!

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Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

edited

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Dustin L. Howett (@DHowett)
omg i was like panicking thinking i made a huge error, i appreciate that you're so understanding, that's actually so nice, i'm not worried now of actaully making the PRs i want because this whole time i'm just trying to fix my problems but they're way too big to be reviewed in a timely manner 😅

but yea, i'll keep working on this and tag you when i need input.

thank you again, i appreciate your understanding ❤️

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          Handle --windowstyle double-dash in early scan, expand tests

86735ad

The early arg scan only stripped one leading dash, so --windowstyle
hidden was not detected (the key became "-windowstyle" with length 12,
failing the <= "windowstyle".Length check). Add double-dash stripping
to match the full parser's GetSwitchKey behavior.

Remove misleading comment claiming colon syntax is handled by the full
parser (GetSwitchKey does not split on colons for windowstyle).

Rewrite manifest test to extract embedded manifest from PE binary
instead of checking a source file that doesn't exist in $PSHOME.

Add 5 early arg scan variant tests: -w, -win, --windowstyle,
/windowstyle, UPPERCASE. Total: 12 Pester tests.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Ryan Yates (kilasuit) added WG-Engine

core PowerShell engine, interpreter, and runtime

CL-Engine

Indicates that a PR should be marked as an engine change in the Change Log

WG-NeedsReview Needs a review by the labeled Working Group labels

Mar 28, 2026

Ahmed Taha (SufficientDaikon) mentioned this pull request

Mar 29, 2026

Document -WindowStyle Hidden behavior change on Windows 11 24H2+ MicrosoftDocs/PowerShell-Docs#12897

Open

Dongbo Wang (daxian-dbw) requested a review from Copilot

March 30, 2026 17:36

Copilot started reviewing on behalf of Dongbo Wang (daxian-dbw)

March 30, 2026 17:54

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Pull request overview

This PR aims to eliminate the visible console window “flash” when launching pwsh -WindowStyle Hidden on newer Windows builds by opting into detached console allocation via the app manifest and proactively allocating the console in Main() using AllocConsoleWithOptions.

Changes:

Add consoleAllocationPolicy=detached to pwsh’s embedded manifest to prevent OS auto-allocating a visible console on Win11 24H2+.
Add AllocConsoleWithOptions interop helpers and use them during early console initialization and hidden-console allocation.
Add a new Pester test file intended to validate manifest and -WindowStyle Hidden behavior.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
`assets/pwsh.manifest`	Opts into detached console allocation policy on newer Windows builds.
`src/System.Management.Automation/engine/Interop/Windows/AllocConsoleWithOptions.cs`	Introduces P/Invoke + helpers for `AllocConsoleWithOptions`.
`src/Microsoft.PowerShell.ConsoleHost/host/msh/ManagedEntrance.cs`	Adds early console allocation logic prior to `EarlyStartup.Init()`.
`src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleControl.cs`	Makes `SetConsoleMode` resilient when no console window handle exists.
`src/System.Management.Automation/engine/NativeCommandProcessor.cs`	Prefers allocating a hidden console via `AllocConsoleWithOptions(NoWindow)` when needed.
`test/powershell/Host/WindowStyleHidden.Tests.ps1`	Adds tests for manifest presence and `-WindowStyle Hidden` behavior.

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src/System.Management.Automation/engine/NativeCommandProcessor.cs

Comment on lines +2492 to +2516

		// Try AllocConsoleWithOptions with NoWindow mode first to avoid the flash
		// that the AllocConsole() + ShowWindow(SW_HIDE) pattern causes.
		bool allocated = Interop.Windows.TryAllocConsoleNoWindow();

		bool returnValue;
		if (hwnd == nint.Zero)
		if (!allocated)
		{
		returnValue = false;
		}
		else
		{
		returnValue = true;
		// Fallback for older Windows: allocate and then hide.
		Interop.Windows.AllocConsole();
		hwnd = Interop.Windows.GetConsoleWindow();
		if (hwnd == nint.Zero)
		{
		return false;
		}

		Interop.Windows.ShowWindow(hwnd, Interop.Windows.SW_HIDE);
		AlwaysCaptureApplicationIO = true;
		}

		AlwaysCaptureApplicationIO = true;

		if (savedForeground != nint.Zero && Interop.Windows.GetForegroundWindow() != savedForeground)
		{
		Interop.Windows.SetForegroundWindow(savedForeground);
		}

		return returnValue;
		return true;

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AllocateHiddenConsole() now returns true whenever TryAllocConsoleNoWindow() returns true, without verifying that a console was actually allocated/attached. Previously the code validated by checking GetConsoleWindow() after allocation and returned false if it was still zero. To preserve the method’s contract, consider validating console allocation after the NoWindow call and falling back (or returning false) if no console is present.

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          Fix Pester 4 compat: move -Skip from Context to It blocks

87933d3

CI uses Pester 4.x which does not support -Skip on Context blocks,
causing 'A parameter cannot be found that matches parameter name Skip'
on all three platforms.

Move -Skip:(!$IsWindows) to individual It blocks (standard pattern).

Also addresses Copilot review feedback:
- Add CI tag so tests run in standard CI (not just Others)
- Remove Assembly::LoadFile path (pwsh.exe is native, not managed)
- Use repo-relative path via $PSScriptRoot for manifest fallback
- Add return after Set-ItResult -Skipped per Pester guidance

Co-authored-by: Copilot <[email protected]>

Dongbo Wang (daxian-dbw) reviewed

Mar 30, 2026

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Dustin L. Howett (DHowett) commented Mar 30, 2026

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(FWIW, as a note for the author -- I'm not just the person who recommended consoleAllocationPolicy, but the person who designed and implemented it. 🙂 )

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Dongbo Wang (daxian-dbw) reviewed

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src/Microsoft.PowerShell.ConsoleHost/host/msh/ManagedEntrance.cs

Comment on lines +141 to +142

		nint existingConsole = Interop.Windows.GetConsoleWindow();
		if (existingConsole != nint.Zero)

Dongbo Wang (daxian-dbw) Mar 31, 2026

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Dustin L. Howett (@DHowett) If the process is started by CreateProcess with the CREATE_NO_WINDOW flag, it may inherit the existing console session but have no console window created for it, right?

If so, existingConsole would be nint.Zero in that case, and we will call AllocConsoleWithOptions in the new code path. I guess AllocConsoleWithOptions(Default) will return that existing console session, but what will AllocConsoleWithOptions(No_Window) do in that case?

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Ahmed Taha (SufficientDaikon) commented Mar 31, 2026

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(FWIW, as a note for the author -- I'm not just the person who recommended consoleAllocationPolicy, but the person who designed and implemented it. 🙂 )

Wow, how does one go about designing and architecting something that'll be used by millions? where do you even start so you make sure people's computers don't like... explode? xD

Dongbo Wang (@daxian-dbw) thank you so much for feedback, very very helpful, you're mentioning things i haven't even thought of.

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Ahmed Taha (SufficientDaikon) force-pushed the fix/windowstyle-hidden-console-flash branch 2 times, most recently from 4a930c9 to 4050f51 Compare

March 31, 2026 07:14


          Address reviewer feedback from daxian-dbw and DHowett

EarlyConsoleInit: remove early ShowWindow(SW_HIDE) for existing consoles
per daxian-dbw — leave -WindowStyle handling to the existing SetConsoleMode
code path. EarlyConsoleInit now only handles the no-console case.

TryAllocConsoleWithMode: check AllocConsoleResult instead of discarding it.
Return false when result is NoConsole (DETACHED_PROCESS respected) so
callers know a console was not actually allocated.

NativeCommandProcessor: add comment clarifying foreground window restore
runs for both NoWindow and fallback paths.

Manifest: add XML comment explaining why asm.v3 xmlns is required on
the application element (distinct from root asm.v1 namespace).

Co-authored-by: Copilot <[email protected]>

Ahmed Taha (SufficientDaikon) force-pushed the fix/windowstyle-hidden-console-flash branch from 4050f51 to 6214139 Compare

March 31, 2026 07:43


          Merge branch 'master' into fix/windowstyle-hidden-console-flash

add7938

Dustin L. Howett (DHowett) commented Mar 31, 2026

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where do you even start so you make sure people's computers don't like... explode? xD

Hah, well, the jury is still out on whether I've made any computers explode. :)

Honestly though... this has been a problem that bugged me for years and years. I wrote a spec (here), forgot about it, sent it to people to get their opinions, promoted it on Twitter, got a few responses, let it sit for multiple years (it was written in 2020 and completed in 2023!)... and then when it seemed like everything was agreed, started writing the code.

Then we had a Microsoft-internal "API review" and the AllocConsoleWithOptions API changed a good amount between what I originally wrote and what we finally shipped.

If you want to see all the gory discussion details, they're over here: microsoft/terminal#7337

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Ahmed Taha (SufficientDaikon) commented Mar 31, 2026

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If you want to see all the gory discussion details, they're over here: microsoft/terminal#7337

You really didn't have to ask, i love this stuff, looks like I have reading material for tonight, thanks for sharing!

I'm always interested in learning how engineers solve the problems they find often times there's a fun story that comes a along with it, and it always fun to see how people even come up with soultions in the first place it been helping me in thinking how to solve my own problems, even none software people have problems to solve and they come up with soultions that I wouldn't even think to consider, so yeah I'm really excited to read that pr.

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Heiko (htcfreek) commented Apr 2, 2026

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Nice. ♥️ Will this get backported to PowerShell 5.1?

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Ahmed Taha (SufficientDaikon) commented Apr 2, 2026 •

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Nice. ♥️ Will this get backported to PowerShell 5.1?

Idk, I made this for me, but if there's a lot of people still on older versions I don't mind doing the work to backport. Lemme lookup how many powershell users are still on older versions

Edit: ooof okay, yea I'll see what I can do xD

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Apr 10, 2026

Ahmed Taha (SufficientDaikon) commented Apr 10, 2026

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Oh, yea, i forgot, I'm gonna see if I can backport this

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Ahmed Taha (SufficientDaikon) commented Apr 16, 2026

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Nice. ♥️ Will this get backported to PowerShell 5.1?

So bad news, can't back port that far

Good news, I'll just add a migration guide in the docs, you may as well update at this point.

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Ahmed Taha (SufficientDaikon) commented Jun 6, 2026

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Dustin L. Howett (@DHowett) is there something holding this up? Need to put on my CV "I'm an open source contributer" and it be true xD

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Justin Chung (jshigetomi) commented Jun 26, 2026

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Ahmed Taha (@SufficientDaikon) Great work here! Seems like this has been thoroughly reviewed and comments addressed.

LGTM

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Justin Chung (jshigetomi) approved these changes

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Comment thread

src/System.Management.Automation/engine/Interop/Windows/AllocConsoleWithOptions.cs Resolved

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test/powershell/Host/WindowStyleHidden.Tests.ps1 Resolved

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Ahmed Taha (SufficientDaikon) and others added 3 commits

July 22, 2026 17:20


          Merge branch 'master' into fix/windowstyle-hidden-console-flash


          Address review feedback on console allocation

6b44701

Cache AllocConsoleWithOptions availability in a static field so later calls
skip the P/Invoke and its exception once the API is known to be missing,
matching the s_WNetApiNotAvailable pattern in WNetGetConnection.cs.

Restore the foreground window on the AllocateHiddenConsole early-return path.
AllocConsole() can shift focus even when GetConsoleWindow() returns zero, so
the restore now runs on every path that captured it.

Remove the AllocConsoleWithOptions probe test. It asserted only that a
bool-returning method returns a bool, so it passed regardless of the fix.


          Merge branch 'master' into fix/windowstyle-hidden-console-flash

8b2913a

Dustin L. Howett (DHowett) commented Jul 28, 2026

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(FYI: I am not on the powershell team, and so I cannot actually meaningfully approve this PR such that it would merge.)

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          Merge branch 'master' into fix/windowstyle-hidden-console-flash

29560fa

Ahmed Taha (SufficientDaikon) commented Aug 3, 2026

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(FYI: I am not on the powershell team, and so I cannot actually meaningfully approve this PR such that it would merge.)

i see.

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Justin Chung (jshigetomi) approved these changes

Aug 14, 2026

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Ahmed Taha (SufficientDaikon) added 2 commits

August 15, 2026 00:26


          Merge branch 'master' into fix/windowstyle-hidden-console-flash

76e8650


          Merge branch 'master' into fix/windowstyle-hidden-console-flash

c938459

Michael Klement (mklement0) commented Nov 9, 2026

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Dustin L. Howett (@DHowett), as an aside re:

whereas AllocConsoleWithOptions with ALLOC_CONSOLE_MODE_DEFAULT will respect DETACHED_PROCESS.

As of this writing, PowerShell actually quietly aborts on startup when launched with DETACHED_PROCESS, as it unconditionally looks for a console and aborts if it cannot find one, without logging a WER event and with spurious exit code 0

Launching pwsh.exe without a console (DETACHED_PROCESS) results in quiet startup failure #28383

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Dustin L. Howett (DHowett) commented Nov 9, 2026

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As of this writing, PowerShell actually quietly aborts on startup when launched with DETACHED_PROCESS,

That seems significantly less than ideal. 😱

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PR Summary

Changes

Behavior by launch context

How EarlyConsoleInit decides what to do

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Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

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How `EarlyConsoleInit` decides what to do

Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

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Ahmed Taha (SufficientDaikon) commented Mar 28, 2026 •

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