firefox title bar cannot be turned off in 21.04

[Chris Hermansen]

Today a Firefox update was pushed out for 21.04. Not sure if this problem occurred with the update or before, but I just noticed it after the update.

Using the Firefox hamburger menu, then selecting Customize toolbar... I arrive at a tab titled Customize Firefox. In the lower left corner of the screen is a checkbox for Titlebar.

If that checkbox is checked, the titlebar appears at the top of the window, and below it are all the tabs.

If that checkbox is NOT checked, the titlebar remains visible but now the window controls are duplicated on the tabs line (in my case to the left as I have the window control position set to the left).

In previous versions of Firefox, it was nice to be able to turn off the titlebar and have the controls move to the tabs line. And in any case, two sets of active window controls, one beneath the other, is not particularly useful.

ProblemType: Bug
DistroRelease: Ubuntu 21.04
Package: firefox 87.0+build3-0ubuntu4
ProcVersionSignature: Ubuntu 5.11.0-14.15-generic 5.11.12
Uname: Linux 5.11.0-14-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
AddonCompatCheckDisabled: False
ApportVersion: 2.20.11-0ubuntu64
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: clh 1415 F.... pulseaudio
 /dev/snd/controlC0: clh 1415 F.... pulseaudio
BuildID: 20210318103112
CasperMD5CheckResult: pass
Channel: Unavailable
CurrentDesktop: ubuntu:GNOME
Date: Wed Apr 14 15:30:39 2021
ForcedLayersAccel: False
InstallationDate: Installed on 2021-04-10 (4 days ago)
InstallationMedia: Ubuntu 21.04 "Hirsute Hippo" - Beta amd64 (20210408)
IpRoute:
 default via 192.168.1.254 dev enp5s0 proto dhcp metric 100
 169.254.0.0/16 dev enp5s0 scope link metric 1000
 192.168.1.0/24 dev enp5s0 proto kernel scope link src 192.168.1.13 metric 100
MostRecentCrashID: bp-61d2fae9-da3a-417f-9fe1-917de0180212
PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:352
PrefSources: prefs.js
Profiles: Profile0 (Default) - LastVersion=87.0/20210318103112 (In use)
RunningIncompatibleAddons: True
SourcePackage: firefox
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/06/2020
dmi.bios.release: 5.14
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: F12e
dmi.board.asset.tag: Default string
dmi.board.name: X570 AORUS PRO WIFI
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrF12e:bd03/06/2020:br5.14:svnGigabyteTechnologyCo.,Ltd.:pnX570AORUSPROWIFI:pvr-CF:rvnGigabyteTechnologyCo.,Ltd.:rnX570AORUSPROWIFI:rvrx.x:cvnDefaultstring:ct3:cvrDefaultstring:
dmi.product.family: Default string
dmi.product.name: X570 AORUS PRO WIFI
dmi.product.sku: Default string
dmi.product.version: -CF
dmi.sys.vendor: Gigabyte Technology Co., Ltd.