Thank you from providing the ability to submit ideas. I'd like the see the ability to remove the Spaces menu icon from the tab bar by using the "Customize feature. I never use the Spaces feature and I'd like to remove the icon.
I understand this likely to be a low priority, but thank you for reading.
Thanks for submitting an idea to the Mozilla Connect community! Your idea is now open to votes (aka kudos) and comments.
While I agree with you, I think the next version of Thunderbird might so radically change the menu and toolbars that we are essentially forced to use the spaces bar.
There are design mockups here https://mzla-thunderbird.invisionapp.com/console/share/4CGY3FJ2WXQ/939370603
There is also a discussion here https://thunderbird.topicbox.com/groups/ux/T289d324313b78e81/thunderbird-114-unified-toolbar
I hope this does not mean that all the non-mailreader stuff will be forced upon users even more. TB is a fine mailreader. All the other stuff is plenty available in other apps and/or not needed at all for most users.
Mail is what I am working with all day. Please allow us to use TB as a mailreader only app!