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Customising the spaces toolbar!

  • 3 replies
  • 5 have this problem
  • 1 view
  • Last reply by Oliver

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Hi there!

I love Thunderbird, especially the new Supernova UI which I'm currently beta testing.

The 'spaces toolbar' has been around for the last couple of major releases, and contains several links I don't need. Is there a way to remove the links to calendar & chat?

Thanks in advance.

Hi there! I love Thunderbird, especially the new Supernova UI which I'm currently beta testing. The 'spaces toolbar' has been around for the last couple of major releases, and contains several links I don't need. Is there a way to remove the links to calendar & chat? Thanks in advance.

Chosen solution

However, it can be done if you use a 'userChrome.css' file.

First ensure the following is enabled.

  • Settings > General
  • Scroll to bottom and click on 'Config Editor'
  • In search type: legacy
  • look for this line: toolkit.legacyUserProfileCustomizations.stylesheets
  • If it is 'False' then toggle to 'True'


  • Help > Troubleshooting Information
  • Under 'Application Basics' - half way - Profile Folder - click on 'Open Folder'

A new window opens showing contents of profile name folder.

  • Exit Thunderbird now this is important

In the beta profile folder create a new folder called chrome (all lower case)

Open Notepad a simple text editor

Copy all the code between the following lines


/* Spaces Toolbar - Customise - Hide */

#calendarButton, #chatButton {
display: none !important; 
}

Save the file as userChrome.css (all lower case except capital C as shown) in the chrome folder

Start Thunderbird.

Read this answer in context 👍 2

All Replies (3)

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Not at the moment. In my case I would like to display the 'Addons & Themes' but hide the 'chat'. I've put forward a bug enhancement request. https://bugzilla.mozilla.org/show_bug.cgi?id=1838257

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Chosen Solution

However, it can be done if you use a 'userChrome.css' file.

First ensure the following is enabled.

  • Settings > General
  • Scroll to bottom and click on 'Config Editor'
  • In search type: legacy
  • look for this line: toolkit.legacyUserProfileCustomizations.stylesheets
  • If it is 'False' then toggle to 'True'


  • Help > Troubleshooting Information
  • Under 'Application Basics' - half way - Profile Folder - click on 'Open Folder'

A new window opens showing contents of profile name folder.

  • Exit Thunderbird now this is important

In the beta profile folder create a new folder called chrome (all lower case)

Open Notepad a simple text editor

Copy all the code between the following lines


/* Spaces Toolbar - Customise - Hide */

#calendarButton, #chatButton {
display: none !important; 
}

Save the file as userChrome.css (all lower case except capital C as shown) in the chrome folder

Start Thunderbird.

Modified by Toad-Hall

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Amazing, thank you so much!