Bug#838793: libgtk-3-0: Menus are too small in GNOME on Wayland

[Tony Houghton]

Package: libgtk-3-0
Version: 3.22.0-1
Severity: important

Since upgrading to 3.22 (I think I was using 3.21 before) many, but not
all, GTK3 applications have broken menus in Wayland. They open very
small with only enough vertical room for scroll arrows and one item, or
less, and far narrower than necessary. Positioning is also incorrect,
and there seems to be some corruption of the content too.

This could be a HiDPI issue because I'm using a Mac Retina, but I
haven't checked another system yet. The affected apps also seem to
ignore the window scaling setting in gnome-tweak-tool, as if it's
hardwried at 2.

One unaffected app is vim-gtk3. I noticed it still depends on gtk 3.19,
so could it be that only apps which have been recompiled against 3.22
are affected?

Launching gedit from a terminal and opening its popup menu shows these
errors:

(gedit:3498): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to
underallocate toplevel GtkWindow 0x5615ae656a40. Allocation is 92x115,
but minimum required size is 173x41.

(gedit:3498): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to
underallocate GtkWindow's child GtkMenu 0x5615aeb4cb40. Allocation is
80x103, but minimum required size is 161x29.

(gedit:3498): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to
underallocate GtkMenuItem's child GtkAccelLabel 0x5615aeb0fd90.
Allocation is 43x17, but minimum required size is 54x17.

(gedit:3498): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to
underallocate GtkMenu's child GtkMenuItem 0x5615af33a190. Allocation is
80x25, but minimum required size is 111x25.

(gedit:3498): Gtk-WARNING **: gtk_widget_size_allocate(): attempt to
underallocate GtkMenuItem's child GtkAccelLabel 0x5615af2d4b70.
Allocation is 17x17, but minimum required size is 73x17.

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'stable-updates'), (500, 'unstable'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.7.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages libgtk-3-0 depends on:
ii  adwaita-icon-theme                      3.22.0-1
ii  hicolor-icon-theme                      0.15-1
ii  libatk-bridge2.0-0                      2.20.1-4
ii  libatk1.0-0                             2.22.0-1
ii  libc6                                   2.24-3
ii  libcairo-gobject2                       1.14.6-1+b1
ii  libcairo2                               1.14.6-1+b1
ii  libcolord2                              1.3.3-2
ii  libcups2                                2.2.0-2
ii  libepoxy0                               1.3.1-1
ii  libfontconfig1                          2.11.0-6.7
ii  libfreetype6                            2.6.3-3+b1
ii  libgdk-pixbuf2.0-0                      2.36.0-1
ii  libglib2.0-0                            2.50.0-1
ii  libgtk-3-common                         3.22.0-1
ii  libjson-glib-1.0-0                      1.2.2-1
ii  libpango-1.0-0                          1.40.3-2
ii  libpangocairo-1.0-0                     1.40.3-2
ii  libpangoft2-1.0-0                       1.40.3-2
ii  librest-0.7-0                           0.8.0-1
ii  libsoup2.4-1                            2.56.0-1
ii  libwayland-client0                      1.11.0-2
ii  libwayland-cursor0                      1.11.0-2
ii  libwayland-egl1-mesa [libwayland-egl1]  12.0.3-1
ii  libx11-6                                2:1.6.3-1
ii  libxcomposite1                          1:0.4.4-1
ii  libxcursor1                             1:1.1.14-1+b1
ii  libxdamage1                             1:1.1.4-2+b1
ii  libxext6                                2:1.3.3-1
ii  libxfixes3                              1:5.0.2-1
ii  libxi6                                  2:1.7.6-1
ii  libxinerama1                            2:1.1.3-1+b1
ii  libxkbcommon0                           0.6.1-1
ii  libxml2                                 2.9.4+dfsg1-2
ii  libxrandr2                              2:1.5.0-1
ii  shared-mime-info                        1.7-1

Versions of packages libgtk-3-0 recommends:
ii  libgtk-3-bin  3.21.5-3

Versions of packages libgtk-3-0 suggests:
ii  gvfs             1.30.0-1
ii  librsvg2-common  2.40.16-1

-- no debconf information