DMARC-Filter:	OpenDMARC Filter v1.4.2 delorie.com 58RLIPpq1040485
Authentication-Results:	delorie.com; dmarc=pass (p=none dis=none) header.from=cygwin.com
Authentication-Results:	delorie.com; spf=pass smtp.mailfrom=cygwin.com
DKIM-Filter:	OpenDKIM Filter v2.11.0 delorie.com 58RLIPpq1040485
Authentication-Results:	delorie.com;
	dkim=pass (1024-bit key, unprotected) header.d=cygwin.com header.i=@cygwin.com header.a=rsa-sha256 header.s=default header.b=cRdpM2ny
X-Recipient:	archive-cygwin AT delorie DOT com
DKIM-Filter:	OpenDKIM Filter v2.11.0 sourceware.org 786FC3858C30
DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1759007903;
	bh=sFGFnyBePHzKXLBJqgbc723dzFAHASy25FBUZAYhiSA=;
	h=Date:Subject:To:List-Id:List-Unsubscribe:List-Archive:List-Post:
	List-Help:List-Subscribe:From:Reply-To:From;
	b=cRdpM2nyDufpwxvWE28XpQNvwlUxIlDMhJDe+V/YgPU4eSGxWU+OeOUTPsrXw233/
	bY/dL0q3E77CtjpHOv0vTiw0pzcXtkW12Mxerj7ZKB8k8voOL5WDJB1Uo2EaVA7w+3
	qWduwss6gnnoG4leJJttJPeJjvHycqg4xf+mQ9Os=
X-Original-To:	cygwin AT cygwin DOT com
Delivered-To:	cygwin AT cygwin DOT com
DMARC-Filter:	OpenDMARC Filter v1.4.2 sourceware.org 6C0AD3858C56
ARC-Filter:	OpenARC Filter v1.0.0 sourceware.org 6C0AD3858C56
ARC-Seal:	i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1759007878; cv=none;
	b=eYbMu/tAGMXW50mCqWE1xBVqtZkpoBdfWZDj3WShUqV4ohH2EDhzGfY2mds24Iq89mVftNsBxi+iBmqCZWZJQ/w+X2je0OOTuqMqplIDzW4pztRER7AGGy4/FLpBvQnUZyKF2OG+G3r9nJo+BAi6h0ZK031oTTRcRPs0LxtHmhI=
ARC-Message-Signature:	i=1; a=rsa-sha256; d=sourceware.org; s=key;
	t=1759007878; c=relaxed/simple;
	bh=q8NIFrniuCR/sh2CQbaFA07c7SpkZPhMlGanQKzOK6I=;
	h=DKIM-Signature:Message-ID:Date:MIME-Version:From:Subject:To;
	b=NsOFRVJOdAk5Gp3k81H5ws0tK2F26hnSkTCG/dwKlKvcodcbBQhLhVIeja6TiCWp+P6KJSoZeMG4QsLgSxx/Q2XGVncn6KL2TRS9yc5IYRj9CocsEKx7DQH9UFZkju8MCKuRDIlcNSpWkWb7nLo9Gw8TqLwyc2jNndF8coBYro0=
ARC-Authentication-Results:	i=1; server2.sourceware.org
DKIM-Filter:	OpenDKIM Filter v2.11.0 sourceware.org 6C0AD3858C56
DKIM-Filter:	OpenDKIM Filter v2.11.0 stargate.mehconsulting.com 58RLHsqG049534
Message-ID:	<a8a9ce6d-5267-4944-afb2-e388d42350b6@mehconsulting.com>
Date:	Sat, 27 Sep 2025 14:17:54 -0700
MIME-Version:	1.0
User-Agent:	Mozilla Thunderbird
Subject:	XWin server is starting but creating a large black opaque rectangular
	area on the desktop
X-Mozilla-News-Host:	news://news.gmane.io
To:	cygwin AT cygwin DOT com
X-BeenThere:	cygwin AT cygwin DOT com
X-Mailman-Version:	2.1.30
List-Id:	General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Archive:	<https://cygwin.com/pipermail/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe:	<https://cygwin.com/mailman/listinfo/cygwin>,
	<mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From:	Mark Hansen via Cygwin <cygwin AT cygwin DOT com>
Reply-To:	Mark Hansen <mark AT mehconsulting DOT com>
Sender:	"Cygwin" <cygwin-bounces~archive-cygwin=delorie DOT com AT cygwin DOT com>

I've been using cygwin with XWin server for decades. On one of my Windows 11 laptops, I'm
running into a problem where upon launching the XWin server, I see a large black filled-in
rectangle (opaque) which fills about 20% of the display. This rectangle has no decorations,
so there is no way to grab/resize/move/identify it. It doesn't allow me to see through it to
the desktop below.

I just updated the cygwin installation on this laptop using the setup-x86_64.exe, version 2.934
and the installation shows I got cygwin.dll version 3.4.10 (based on the cygcheck -s -v -r output).

I launch the X server using the following command:

    C:\Apps\cygwin\bin\run.exe --quote /usr/bin/bash.exe -l -c "cd; exec /usr/bin/startxwin -- -listen tcp -emulate3buttons"

This black rectangle issue is newly noticed as I just started trying to use a new large display
connected to the PC via a USB to HDMI adapter.

I've been noticing on my other Windows PC that from time to time, there is a region roughly the same
size where although I can see the desktop, I'm unable to click through to any of the shortcuts in
the region. I now think that region is the same rectangle - it's just that it's not black and opaque
on the other PC, and it doesn't do it all the time. When I notice this happening, I usually just stop
the X Server and restart it and it's fine.

On this problem laptop, each time I start the X Server, the black, opaque rectangle appears, but it
seems to only happen when I'm displaying to a second display via a USB - HDMI display adapter or
viewing the laptop via an RDP session. When I'm accessing the laptop native display directly, the
X Server seems to start just fine and there is no black rectangle.

I keep the XServer running through the use of the .startxwinrc file in my HOME directory. This
file includes a single line used to launch an executable "xnoexit.exe" application, which is basically
just a compiled C program that does a sleep forever which allows the X Server to keep running
until commanded to exit. I did replace that xnoexit.exe command with a simple /usr/bin/xload command
to make sure that wasn't the issue. When I did that, I saw the xload application launch, so I can
see the change worked, but the black rectangle still appeared while the X Server was running.

Is there any way to determine what is causing this? I really want to be able to use this laptop
while displaying via the USB -> HDMI adapter to the second display, as it's a much larger
display (3840x1600), which is much nicer to use than the laptop's native 1920x1080 display.


-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple

- Raw text -