Firefox - CTRL or SHIFT or ALT not working in Guest VM


Well-Known Member
Aug 4, 2017
Proxmox 6.4 / Firefox 88.0.1

My journey with Firefox issues continues. Now I'm unable to use CTRL- or SHIFT- or ALT -keys in the console of a guest in Firefox. In Chromium it works just fine. Each of these do not work and it's not a matter of the issues with CTRL-ALT-SHIFT issues in the past.

Does anyone experience the same issue?
Does the problem occur with only one VM or all VMs?

Are you use SPICE or noVNC?

Please post a full output of the pveversion -v also the VM config qm config <VMID>

Thank you for the quick reply. Unfortunately, the issue appears in all virtual machines after upgrade to 6.4-4. I also tested and upgraded to 6.4-5 and have the same problem. I'm using noVNC exclusively. Maybe the issue startet together with Firefox 88.

Here I'm posting the output of pvmversion -v of one of the hosts. They are all the same.

root@pve1:~# pveversion -v
proxmox-ve: 6.4-1 (running kernel: 5.4.106-1-pve)
pve-manager: 6.4-5 (running version: 6.4-5/6c7bf5de)
pve-kernel-5.4: 6.4-1
pve-kernel-helper: 6.4-1
pve-kernel-5.4.106-1-pve: 5.4.106-1
pve-kernel-5.4.103-1-pve: 5.4.103-1
pve-kernel-5.4.73-1-pve: 5.4.73-1
ceph-fuse: 12.2.11+dfsg1-2.1+b1
corosync: 3.1.2-pve1
criu: 3.11-3
glusterfs-client: 5.5-3
ifupdown: residual config
ifupdown2: 3.0.0-1+pve3
ksm-control-daemon: 1.3-1
libjs-extjs: 6.0.1-10
libknet1: 1.20-pve1
libproxmox-acme-perl: 1.0.8
libproxmox-backup-qemu0: 1.0.3-1
libpve-access-control: 6.4-1
libpve-apiclient-perl: 3.1-3
libpve-common-perl: 6.4-2
libpve-guest-common-perl: 3.1-5
libpve-http-server-perl: 3.2-1
libpve-storage-perl: 6.4-1
libqb0: 1.0.5-1
libspice-server1: 0.14.2-4~pve6+1
lvm2: 2.03.02-pve4
lxc-pve: 4.0.6-2
lxcfs: 4.0.6-pve1
novnc-pve: 1.1.0-1
proxmox-backup-client: 1.1.5-1
proxmox-mini-journalreader: 1.1-1
proxmox-widget-toolkit: 2.5-3
pve-cluster: 6.4-1
pve-container: 3.3-5
pve-docs: 6.4-1
pve-edk2-firmware: 2.20200531-1
pve-firewall: 4.1-3
pve-firmware: 3.2-2
pve-ha-manager: 3.1-1
pve-i18n: 2.3-1
pve-qemu-kvm: 5.2.0-6
pve-xtermjs: 4.7.0-3
qemu-server: 6.4-2
smartmontools: 7.2-pve2
spiceterm: 3.1-1
vncterm: 1.6-2
zfsutils-linux: 2.0.4-pve1

Additionally I provide two config outputs of 2 vm's.

oot@prox2:~# qm config 1001
agent: 1
balloon: 4096
boot: order=scsi0;net0
cores: 4
cpu: host,flags=+aes
memory: 16382
name: port0
net0: virtio=6E:BB:87:24:53:14,bridge=vmbr0,firewall=1
numa: 1
onboot: 1
ostype: l26
protection: 1
scsi0: VM:vm-1001-disk-0,cache=writeback,discard=on,iothread=1,size=50G,ssd=1
scsihw: virtio-scsi-single
smbios1: uuid=dd38b8e8-f12d-4acb-ac6b-83d6f44b30ac
sockets: 2
startup: order=1,up=10
vmgenid: 95aaa35f-b315-417a-9789-f4842b5b9ecd


root@pve1:~# qm config 800
agent: 1
bios: seabios
boot: order=scsi0
cores: 8
cpu: host
memory: 32768
name: nh-fun2build0
net0: e1000=16:05:16:2E:62:14,bridge=vmbr0,firewall=1
numa: 1
ostype: l26
scsi0: VM:vm-800-disk-0,cache=writeback,iothread=1,size=100G,ssd=1
scsihw: virtio-scsi-single
smbios1: uuid=055e14b3-3214-412a-8c9a-91a165f63f68
sockets: 2
vga: vmware,memory=512
vmgenid: 383f9366-dd61-4a53-9b9a-9cfbcff51e7c
Thank you for the VM configs and the version.

I just tested it on my workstation the keys on Firefox 88.0.1 (OS Ubuntu) the SHIFT, ALT and CTRL are works.

Have you tried to open noVNC on a different browser?

Yes, as mentioned in the opening thread, Chromium works. Tested other browsers as well. But they are all Chromium-based. It's just Firefox. Just wondering what the issue is and where to look for settings to be changed.

Any advice?

Yes, as mentioned in the opening thread, Chromium works. Tested other browsers as well. But they are all Chromium-based. It's just Firefox. Just wondering what the issue is and where to look for settings to be changed.

Any advice?
maybe a plugin/extension on firefox messing with the keys?
  • Like
Reactions: Moayad
Unfortunately, even with all addon's disabled I have the same issue. Also, there is no difference between FF on Windows and/or Linux. I almost ruled out everything that could point to a problem on the host itself. But other browsers don't show the issue and even different plaforms make no difference with FF.


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