Rated 4 out of 5 stars

CSS to hide button text in userChrome.css:

.extension-action > div:nth-child(1) > button:nth-child(1) {
font-size: 0 !important;
}

Rated 4 out of 5 stars

This is a well crafted addon and does exactly what is needed. One recommendation would be to allow for renaming the button text - Toggle Folder Pane is a little long for a button. If you can add that as a setting this would be a 5 star addon!

Rated 5 out of 5 stars

Like this a lot. Just wish the button was incorporated into the Spaces Toolbar instead.