Battery-low notification bubble does not appear on top of Youtube full-screen videos in Xenial

While I was watching a full-screen video on Youtube, I heard the battery-low notification sound, but I did not see the bubble on top of the video. I think it is important to show the bubble on top of full-screen videos.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: notify-osd 0.9.35+16.04.20160415-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-57.78-generic 4.4.35
Uname: Linux 4.4.0-57-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.1-0ubuntu2.4
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Dec 23 19:54:48 2016
DesktopSession: 'ubuntu'
GtkTheme: 'Ambiance'
IconTheme: 'ubuntu-mono-dark'
InstallationDate: Installed on 2016-04-26 (240 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
MachineType: Acer Aspire E5-551G
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-57-generic.efi.signed root=UUID=b086e465-55d5-4029-8fcb-5a17bfffe234 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 xserver-xorg 1:7.7+13ubuntu3
 libgl1-mesa-glx 11.2.0-1ubuntu2.2
 libdrm2 2.4.67-1ubuntu0.16.04.2
 xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1.2
 xserver-xorg-video-ati 1:7.7.0-1
SourcePackage: notify-osd
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/06/2015
dmi.bios.vendor: Insyde Corp.
dmi.bios.version: V1.15
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: EA50_KV
dmi.board.vendor: Acer
dmi.board.version: V1.15
dmi.chassis.asset.tag: Chassis Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.15:bd07/06/2015:svnAcer:pnAspireE5-551G:pvrV1.15:rvnAcer:rnEA50_KV:rvrV1.15:cvnAcer:ct10:cvrChassisVersion:
dmi.product.name: Aspire E5-551G
dmi.product.version: V1.15
dmi.sys.vendor: Acer
glxinfo: Error: [Errno 2] No such file or directory: 'glxinfo'