Use the code in the topic cited in your post, but copy it into a userChrome.css file, not a userContent.css file.

Thank you sfhowes I used what I thought was the code atttached to no avail. My steps are Open Profile Directory - Close TBird - Create Folder chrome - Open chrome folder - Create New Document - Open it - Copy Past code - Save As userChrome.css - Close File & Folder - Config.editor toolkit legacy profile stylesheet = True - Restart TBird . I have also tried Clear startup cache . Could any settings throw It ? Should you have a chance understand if not. Thanks George

Can I ask here about this area of the code what it represents ?? Thanks .

Have partially acheived my aim simply with Settings > General > Fonts & Colors > Colors Button > Text and Background . Not what I was aiming for but some of the way and less sharpness on the eyes . Attached screen shots . Sure the rest will come in time. Thanks George

The namespace line is necessary for some css code. For others, it can be omitted. It's only needed once at the top of the file.

Your code should work for the Folder Pane, but for the Threads Pane, delete the line in green with Threads pane:

See the attached picture that shows the result with this code:

@namespace html url("http://www.w3.org/1999/xhtml");

#folderPane {
background-color: #87CEFA !important;
font-family: Times, serif !important;
color: navy !important;
}

table[is="tree-view-table"]{
background: #87CEFA !important;
font-family: Times, serif !important;
color: navy !important;
}

THANK YOU so much that is great . Attached is my new TB Page and .css file code for this, am very pleased with result maybe fine tune shades. I will do this to my 85 yld mothers PC and it will not only make it easier on the eye but lays it out better. Including if I need to point out something over the phone from different states that we live it will be identified easier. Thanks again George PS : MUST NOT FORGET Settings > General > Config Editor toolkit.legacyUserProfileCustomizations.stylesheets change to true . MAYBE : Clear startup cache.. in Troubleshooting Information