New: Pipeline 8 with CSS Variables and Prince 13

Today, we’re releasing Pipeline 8 with support for Prince 13, a major upgrade to our HTML-to-PDF conversion engine. As a reminder, to avoid any breaking changes, we never automatically upgrade your documents. Existing users will need to test and upgrade to Pipeline 8 in order to use Prince 13.

You can change your default pipeline in your account settings page, or via the pipeline parameter in your API calls. Using the account setting is convenient, while the API parameter lets you test individual documents before upgrading your entire account. Pipelines often contain breaking changes, so we strongly recommend reviewing the release notes and testing your documents before changing your settings.

Some of Prince 13’s changes include:

  • Support for CSS variables (aka custom properties)
  • Flex box single-column and row containers can now break across pages
  • The default behavior for line-height has changed, see below for more information
  • Improved placement and sizing of SVG embedded images
  • Support for SVGs without intrinsic width/height or aspect ratio
  • Support for fragmenting single-column/row flex containers across multiple pages
  • Support for the CSS3 box-shadow and text-shadow properties
  • Accept -prince- as a vendor prefix for Prince-specific CSS properties and @-prince for at-rules like @-prince-pdf and @-prince-color
  • Support for new background-attachment: fixed bleed mechanism for extending the @page background into the bleed area
  • SVG images can now be reused without increasing PDF file size
  • Support for WOFF2 fonts
  • Support for the object-fit and object-position properties


Prince 13 changes the behavior of line-height: normal; to honor the recommended value from the current font. This change allows your documents to match more closely with how your input html looks in a web browser. When upgrading from a previous pipeline you can expect line heights to be a little different.  Customers who prefer the old behavior can get it back by specifying line-height: 1.2;.

A full list of changes and fixes are available in Prince’s release notes.

Try it out today and let us know what you think at And if there are other new features you need, don’t hesitate to ask.