Minor Font Change

I would like the font for the e-mail columns headings IE: the words Subject, Correspondents, Date, etc, to be changed to contrast with the text in those columns. I suggest using a larger, bold and coloured font like this. Thanks for considering - William

A userChrome with this code:

   #subjectCol{background-color:yellow !important; -moz-appearance: none ! important;
font-weight: bold !important;
color: red !important;}

This changes the Subject text to red bold on a yellow background. Add similar code for #dateCol, #senderCol, #correspondentCol, #recipientCol, #attachmentCol etc.

Create a subfolder of the profile named chrome, in chrome create a file with a text editor, save it as userChrome.css with file type All files, with the above code.
Toggle toolkit.legacyUserProfileCustomizations.stylesheets to true in Config. editor.