How to change the Logo
By default, the logo is located in the roundcube here:/roundcube/skins/default/images
and the file name is
roundcube_logo.png
The easiest thing to do, is to use your favorite image editor, and create a png image that is is 165px x 55px. And name it roundcube_logo.png
Next step is to access your site via FTP/SFTP and change the name of the original file to something like
roundcube_logo.png.old
Then upload your custom image to the same directory. Refresh the browser and bask in the glow of your custom logo!
Change Page Title