Delete key inputs Unicode Delete character (007F) instead of deleting the next character

[Petr Doležal]

When pressed, the delete key inputs the Unicode 007F character instead of deleting the following character. In most cases, this is difficult to see, but in a terminal, the 007F is clearly visible.

The xev output for the key press is following:

KeyPress event, serial 36, synthetic NO, window 0x4200001,
    root 0x5df, subw 0x0, time 81101326, (1403,948), root:(1453,1062),
    state 0x0, keycode 119 (keysym 0xffff, Delete), same_screen YES,
    XLookupString gives 1 bytes: (7f) ""
    XmbLookupString gives 1 bytes: (7f) ""
    XFilterEvent returns: False

KeyRelease event, serial 36, synthetic NO, window 0x4200001,
    root 0x5df, subw 0x0, time 81101443, (1403,948), root:(1453,1062),
    state 0x0, keycode 119 (keysym 0xffff, Delete), same_screen YES,
    XLookupString gives 1 bytes: (7f) ""
    XFilterEvent returns: False

This is a new fresh install of Ubuntu 20.04, I don't remember the delete key working at any point since the installation.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: xorg 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 5.4.0-52.57-generic 5.4.65
Uname: Linux 5.4.0-52-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.9
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: Sat Oct 31 12:54:40 2020
DistUpgraded: Fresh install
DistroCodename: focal
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation UHD Graphics 620 (Whiskey Lake) [8086:3ea0] (prog-if 00 [VGA controller])
   Subsystem: Acer Incorporated [ALI] UHD Graphics 620 (Whiskey Lake) [1025:1312]
InstallationDate: Installed on 2020-10-14 (16 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
MachineType: Acer Swift SF514-53T
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-52-generic root=/dev/mapper/vgubuntu-root ro quiet splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/25/2019
dmi.bios.vendor: Insyde Corp.
dmi.bios.version: V1.09
dmi.board.name: Carlsberg_WL
dmi.board.vendor: WL
dmi.board.version: V1.09
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: V1.09
dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.09:bd04/25/2019:svnAcer:pnSwiftSF514-53T:pvrV1.09:rvnWL:rnCarlsberg_WL:rvrV1.09:cvnAcer:ct10:cvrV1.09:
dmi.product.family: Swift 5
dmi.product.name: Swift SF514-53T
dmi.product.sku: 0000000000000000
dmi.product.version: V1.09
dmi.sys.vendor: Acer
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.101-2
version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.4
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

[Daniel van Vugt (vanvugt)]

That xev output looks correct, I get the same output from 'xev' but don't get this bug.

Does the problem occur in GNOME Terminal or some other terminal app? Also do you have any accessibility settings enabled (look in Settings > Universal Access)?

[Petr Doležal (elkir)]

Happens in every app: Gnome Terminal, Xterm, Chrome, login screen.

It's only in some places, such as terminal or Chrome URL bar where the character displays, but the wrong behaviour is everywhere.

There are no accessibility settings turned on.