See https://support.mozilla.org/en-US/questions/1305077

Thank you. I have set the entry toolkit.legacyUserProfileCustomizations.stylesheets to true in Config. editor. But nothing changed.

I fear perhaps because I have not set up the CSS style sheets code, it is beyond my capability,

Still I want to know how to replace Thunderbird. I cant find anything except the proprietary stuff, that I despise.

Kind regards

Did you do it like this:

In Thunderbird

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

A new window opens showing the contents of your 'profile name' folder.

• Exit Thunderbird now - this is important.

• create a 'chrome' folder spelt all lower case. see first image below showing where it is located.

Open 'Notepad

Copy all the text between the lines below and paste it into Notepad. It is possible you did not copy all the text at the link as the scrollbar could have caused a problem in copying all text.

.calendar-event-box-container[categories] {
margin: 0px !important;
background-position: top left !important;
background-repeat: no-repeat !important;
}

calendar-category-box[categories]{
display: none !important;
}

/* Adapting background color following category */
.calendar-event-box-container[categories="anniversary"] { 
color: black !important; background-color: #F08080 !important;}
.calendar-event-box-container[categories="birthday"] { 
color: black !important; background-color: #e6e6fa !important;}
.calendar-event-box-container[categories="business"] { 
color: black !important; background-color: #FFCC66 !important;}

Please note: where it says eg: #F08080 that is the hex code for a colour. You can change this to whatever you want. The link below can help you choose a colour and get the required hex code.

• https://www.w3schools.com/colors/colors_picker.asp

save the notepad document with this name userChrome.css (all lower case except for the C) in the 'chrome' folder

See example image below Note: the 'userChrome.css' file is Type : Cascading Style Sheet (css) If it says it is Type: text document, then it is possible you have a document called 'userChrome.css.txt' In which case rename the file by removing the .txt, you might get a pop up asking if you really want to do and the answer is yes, you do. If unsure, make sure you have selected the checkbox 'File name extensions' selected - see image below. I have several version so ignore them - it is the one I have shown with red box that is important to you.

If you need to adjust any of the colours in that 'userChrome.css' file. Please make sure you exit Thunderbird first.

As this is a Thunderbird Support Forum used by people who use Thunderbird, I'm not in a position to advise on other email clients as I've have no idea what they may or may not offer that suits all the needs you require. You may find one that offers the calendar colouring without intervention, but then fails to offer something else you may have already in Thunderbird. But since your issue can easily be sorted because Thunderbird can be manually modified and the fact that you otherwise do like Thunderbird. I would hope you review the instructions as it only requires creating a file and a folder and copy pasting text. Give it a go. I've helped many people who seemed daunted by this sort of thing at first, but they succeeded.

You can always post images showing where you created that 'chrome' folder, files it contains and the contents of the 'userChrome.css' file so we can advise.

Hi Tod Thank you for you help. I did as you suggested, see screen shots below. I exited and restarted Thunderbird. But nothing changed

However I noticed my profile folder is C:\Users\Frank\AppData\Roaming\Thunderbird\Profiles\o01030pj.IETimport

So I added the chrome directory and userChrome.css under the \o01030pj.IETimport but nothing changed. see screen shot c below.

The css file is now in both profiles, but make sure the Config. editor toggle is done in the current active profile, o01030pj.IETimport, as each profile has its own preferences.

re :However I noticed my profile folder is C:\Users\Frank\AppData\Roaming\Thunderbird\Profiles\o01030pj.IETimport So I added the chrome directory and userChrome.css under the \o01030pj.IETimport

Yes, that would be correct. I presume you did exit Thunderbird first. Did you also set the config editor preference whilst running that profile ?

agree with sfhowes

Set the entry: toolkit.legacyUserProfileCustomizations.stylesheets to true in Config. editor in both profiles.

Then restart Thunderbird.

Hi Guys. Thanks for the help.

Yesterday the changes had no effect. Today I restarted Thunderbird and bingo it works!!!!

Gotta love User Supported Software.

note to self. Send another donation soonest.

Thunderbird would appreciate your donation, here is a link: https://give.thunderbird.net/en-GB/?utm_source=thunderbird-client&utm_medium=referral&utm_content=help-menu