bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Sébastien Miquel]

Hi,

To reproduce :
  1. Start `emacs -q --daemon`
  2. Start a frame with `emacsclient -c`. At this point, X clipboard
  access works fine and I can copy/paste between emacs and other 
applications.
  3. From Thunar (file manager from xfce), right click a file and `Open
  with` emacsclient (/usr/bin/emacsclient), creating another frame.
     At this point, X clipboard access is broken: I cannot copy/paste
  between emacs and other applications.

In GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 
3.24.31, cairo version 1.17.4)
  of 2022-02-05
Repository revision: 224aeb2877fffc894e9d1b31f7f44db0e55160c3
Repository branch: master
System Description: Arch Linux

Configured using:
  'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
  --localstatedir=/var --mandir=/usr/share/man --with-gameuser=:games
  --with-sound=alsa --with-modules --without-libotf --without-m17n-flt
  --without-gconf --without-gsettings --with-native-compilation
  --with-xinput2 --with-pgtk --without-xaw3d --with-sound=no
  --without-gpm --without-compress-install
  '--program-transform-name=s/\([ec]tags\)/\1.emacs/'
  'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions
  -Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security
  -fstack-clash-protection -fcf-protection'
  LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS HARFBUZZ JPEG JSON LCMS2
LIBSELINUX LIBSYSTEMD LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER
PGTK PNG RSVG SECCOMP SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS WEBP XIM
GTK3 ZLIB

Important settings:
   value of $LC_ALL: en_US.UTF-8
   value of $LANG: en_GB.UTF-8
   locale-coding-system: utf-8-unix

-- 
Sébastien Miquel

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Sébastien Miquel <sebastien.miquel@posteo.eu> writes:

> Hi,
>
> To reproduce :
>  1. Start `emacs -q --daemon`
>  2. Start a frame with `emacsclient -c`. At this point, X clipboard
>  access works fine and I can copy/paste between emacs and other
> applications.
>  3. From Thunar (file manager from xfce), right click a file and `Open
>  with` emacsclient (/usr/bin/emacsclient), creating another frame.
>     At this point, X clipboard access is broken: I cannot copy/paste
>  between emacs and other applications.
>
> In GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
> 3.24.31, cairo version 1.17.4)
>  of 2022-02-05
> Repository revision: 224aeb2877fffc894e9d1b31f7f44db0e55160c3
> Repository branch: master
> System Description: Arch Linux

If you're using X, you shouldn't be using PGTK.  The support provided by
the real X port is miles ahead of what GTK can offer.

That aside, I suspect emacsclient is causing Emacs to open a second
display connection, which causes clipboard access in PGTK to be disabled
due to a GTK bug.

What does (x-display-list) evaluate to in the buggy Emacs, after you
create the other frame which causes the bug?

Thanks.

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Sébastien Miquel]

Po Lu writes:
> If you're using X, you shouldn't be using PGTK.  The support provided by
> the real X port is miles ahead of what GTK can offer.
Is --with-xinput2 supposed to work well without PGTK ? I run into a
separate issue with key bindings that makes it unusable without.
> That aside, I suspect emacsclient is causing Emacs to open a second
> display connection, which causes clipboard access in PGTK to be disabled
> due to a GTK bug.
>
> What does (x-display-list) evaluate to in the buggy Emacs, after you
> create the other frame which causes the bug?
Indeed, (x-diplay-list) originally reports (":0.0"), and after the
second frame is created, (":0.0" ":0").

If the bug is with GTK, can you think of any workaround on my end ?
> Thanks.

Thank you.

-- 
Sébastien Miquel

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

> Is --with-xinput2 supposed to work well without PGTK ? I run into a
> separate issue with key bindings that makes it unusable without.

`--with-xinput2' does nothing on PGTK, but it enables the use of the X
Input Extension on X, which brings support for modern input devices to
the X port.  (And that support is supposed to work better than PGTK,
since you get touchpad gestures and touchscreen support, both of which
aren't available in PGTK on X.)

Please report the separate issue as a bug, if it hasn't been fixed
already on master.

XInput 2 support will eventually be enabled by default, so it's vital
for it to get a lot of testing.

> Indeed, (x-diplay-list) originally reports (":0.0"), and after the
> second frame is created, (":0.0" ":0").

I see you're launching /usr/bin/emacsclient -- emacsclient from a PGTK
build differs from one from a different build, so are you sure it's the
right emacsclient binary?

> If the bug is with GTK, can you think of any workaround on my end ?

I can't, sorry.

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Sébastien Miquel]

Po Lu writes:
> Please report the separate issue as a bug, if it hasn't been fixed
> already on master.
>
Will do.
> I see you're launching /usr/bin/emacsclient -- emacsclient from a PGTK
> build differs from one from a different build, so are you sure it's the
> right emacsclient binary?

Yes, it's the right binary.

The issue must be specific to the way Thunar starts the application.
I've just checked that it works fine when using Nautilus (the GNOME
file manager) instead.

-- 
Sébastien Miquel

bug#53957: 29.0.50; pgtk: starting emacsclient from thunar breaks X clipboard access

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Sébastien Miquel <sebastien.miquel@posteo.eu> writes:

> Will do.

Thanks.

> Yes, it's the right binary.
>
> The issue must be specific to the way Thunar starts the application.
> I've just checked that it works fine when using Nautilus (the GNOME
> file manager) instead.

Thanks, then we should add it to etc/PROBLEMS.  (But please try to find
a workaround first.)