Option grp:alts_toggle does not work

[Sergey]

Setting grp:alts_toggle has effect, but keyboard layouts are not actually switched by pressing both alts.

To reproduce:

$ setxkbmap -verbose 10 -option "" -option grp:alts_toggle
Setting verbose level to 10
locale is C
Trying to load rules file ./rules/evdev...
Trying to load rules file /usr/share/X11/xkb/rules/evdev...
Success.
Applied rules from evdev:
rules: evdev
model: pc105
layout: us,ru,us
variant: ,,
options: grp:alts_toggle
Trying to build keymap using the following components:
keycodes: evdev+aliases(qwerty)
types: complete
compat: complete
symbols: pc+us+ru:2+us:3+inet(evdev)+level3(ralt_switch_for_alts_toggle):1+level3(ralt_switch_for_alts_toggle):3+group(alts_toggle)
geometry: pc(pc105)
$

After which Alt-Alt combo does not switch keyboard layouts.

Gnome's Win-Space setting still works to switch layouts though. Also, setting grp:shifts_toggle using the same method does work as expected.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: x11-xkb-utils 7.7+5
ProcVersionSignature: Ubuntu 5.4.0-91.102-generic 5.4.151
Uname: Linux 5.4.0-91-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
.proc.driver.nvidia.gpus.0000.01.00.0: Error: path was not a regular file.
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 390.144 Wed Jun 2 23:02:41 UTC 2021
 GCC version: gcc version 9.3.0 (Ubuntu 9.3.0-17ubuntu1~20.04)
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CasperMD5CheckResult: skip
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Thu Jan 20 23:27:16 2022
DistUpgraded: 2020-08-12 01:22:19,173 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py'
DistroCodename: focal
DistroVariant: ubuntu
DkmsStatus: nvidia, 390.144, 5.4.0-91-generic, x86_64: installed
GraphicsCard:
 Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. 3rd Gen Core processor Graphics Controller [1043:15a7]
 NVIDIA Corporation GK107M [GeForce GT 650M] [10de:0fd1] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. GeForce GT 650M [1043:15a7]
InstallationDate: Installed on 2020-03-26 (665 days ago)
InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017)
MachineType: ASUSTeK COMPUTER INC. UX51VZA
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-91-generic root=UUID=7976ac28-0b9c-4db0-8548-3d348ac7c552 ro
SourcePackage: x11-xkb-utils
UpgradeStatus: Upgraded to focal on 2020-08-11 (526 days ago)
dmi.bios.date: 12/03/2012
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: UX51VZA.204
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: UX51VZA
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrUX51VZA.204:bd12/03/2012:svnASUSTeKCOMPUTERINC.:pnUX51VZA:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX51VZA:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.family: UX
dmi.product.name: UX51VZA
dmi.product.sku: ASUS-NotebookSKU
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.105-3~20.04.2
version.libgl1-mesa-dri: libgl1-mesa-dri 21.0.3-0ubuntu0.3~20.04.5
version.libgl1-mesa-glx: libgl1-mesa-glx 21.0.3-0ubuntu0.3~20.04.5
version.nvidia-graphics-drivers: nvidia-graphics-drivers-* N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.13-1ubuntu1~20.04.2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1