blank.svg, pause.svg, saved.svg, snow.svg icons by jensbob (https://github.com/jensbob/pdfpc)

pen.svg, highlight.svg, eraser.svg icons by Charles Reiss

snow.svg based on icon by bocian
(http://openclipart.org/detail/30829/snowflake-by-bocian)

locked.svg based on document-encrypted.svg from
https://github.com/KDE/breeze-icons

move.svg is mono-move.svg, linewidth.svg is mono-linewidth.svg, and
settings.svg is settings-button from https://openclipart.org
