Broken tabbox / tabpanels in Linux in TB 60

Hi,

It looks like the XUL Elements tabbox and tabpanels are currently broken for Linux users:

The tabs do not have any border or other visuals, the panel also has no border. I have heard this from multiple Linux users and it is not a theme issue as none of them had any special theme installed.

The last user reporting this to me is running Ubuntu 18.04 LTS with Gnome3 and Thunderbird 60.

Is this a bug in Thunderbird? Can we do something About it, or is it a fault in Linux?

Thanks for your help,
John

I see well defined tabs with borders in my Ubuntu supplied Thunderbird 60.2.1 on Ubuntu 18.04.1 LTS Gnome 3.28.

I barely see them with the Ubuntu supplied Thunderbird 60.2.1 on my Linux Mint 19.1 with the Cinnamon desktop, but they are there.

Also Thunderbird is switching to preferences in a tab in a future version.

You can preview that by opening the Config Editor, search for “mail.preferences.inContent” (without quotes) and toggle the preference. Close preferences, reopen them and you will see a slightly highlighted underlined tab.

Tabbed Preferences

The usage of XUL tabbox is not limited to the TB preferences. It is a standard XUL element used by TB and some Add-ons. I just used the TB preferences as an example everyone can check.

So what is the reason for this behavior? Who is to blame? How can we fix it?

Thanks,

John

I don’t know the reason.

Blame the graphics driver? Don’t know how to fix something I don’t see needs fixing on my system. Anyway I’m not a developer.

Maybe install a daily and see if things you see differently are fixed.

I have well defined tabs with borders.

Where would I check for other problems?

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1
OS: Linux 4.15.0-42-generic
Ubuntu 18.04.1 Gnome 3.28.2
Graphics Card: GeForce GT 630/PCIe/SSE2
Driver: nvidia-driver-390

I see you are using the Ambiance or Radiance theme. I am using the default Adwaita theme.

That is the reason you don’t see the well defined tabs.

I am not a developer either, but I was asked by by a thunderbird developer to create a topic here about this issue. Maybe that was wrong.

I am a Add-on developer and i use a tabbox and many of my users complain about it not being displayed correctly. All of them are Linux users and one of them had send me that screenshot.

I will ask them About the scheme.