Limitations and warnings

In CSS 3 but not (well) supported in pdfChip

While in pdfChip almost all valid CSS3 properties can be used, it does not make sense for some of them. It is obvious that this applies to all dynamic page content like animations.

CSS 3 properties for dynamic page content will have not effect in pdfChip

  • Transitions
  • Animations
  • User-Interface properties
  • Aural Style Sheets (text to speech, sound synthesis)


The CSS 3 properties for columns: column-count, column-gap and column-rule are currenty not supported.

The much more powerfull CSS Regions module should be used instead. The CSS Regions module allows content from one or more elements to flow through one or more boxes.

The CSS 3 Paged Media Module

The Paged Media Module is currently not supported by pdfChip (except for defining page sizes usign the “@page Rule”), nor would that be the case for most of the current browser versions.

The Paged Media Module specifies how pages are generated. It has functionality for page size, margins, orientation, headers and footers, enables page numbering and running headers or footers.

Although the Paged Media Module is not supported it is possible with pdfChip to achieve whatever (in theory) would be possible with this module:

  • To define page sizes use the @page rule (the only Paged Media Module feature supported in pdfChip).
  • Advanced functionality for adding page numbers, running headers and footers the pdfChip overlays should be used, possibly in combination with the pdfChip Dual Pass operating mode.
  • It is even possible to define page paramters that are specific to the print process (page geometry boxes) using special pdfChip custom CSS properties.

In MathML 3 but not (well) supported in pdfChip

callas pdfChip is based on WebKit, and WebKit’s support for MathML 3 is seriously limited. Unless extra steps are taken, callas pdfChip will not do a good job when converting non-trivial MathML to PDF.

To overcome this limitation, use MathJax, a JavaScript library that extends WebKit (as much as most other web engines and browsers) such that presentation MathML is supported almost completely (see “Supported MathML commands” for information about the limitations of MathJax when processing MathML).

Please also keep in mind, that support for “Content MathML” is in essence seriously limited (or “experimental”). While Content MathML is semantically richer than presentation it – going back to its nature – provides much less control over how a formula is presented than Presentation MathML. Thus it comes at no surprise that whenever specifics of how a formula is presented are important, anybody is turning to Presentation MathML anyway, so lack of support for Content MathML usually is not an issue for when creating PDF from HTML 5 and MathML 3.