A user experience plea for more consistency across platforms
Ebook publishing is full of problem areas, most of which cannot be addressed through standardisation but can only come about via a sea-change in the behaviour and nature of the various participants in the ebook industry.
There are, however, several issues that could be addressed, at least partially, via standardisation, that would make everybody’s life easier if implemented.
One of the major issues facing publishers today is the spiralling complexity of dealing with vendor rendering overrides.
Each vendor applies different CSS overrides with differing behaviours, sometimes even only enabling features through server-side manipulation, which means that proper testing of an ebook is not only difficult, but impossible.
If vendors cannot be talked out of requiring these overrides then they need to be standardised and normalised. Any reading system that implements a CSS override is in violation of how the CSS standard defines the cascade and so is in violation of the EPUB 3 standard.
CSS overrides come in four broad types:
- Vendor styles only – The publisher’s styles are completely ignored in favour of the vendor’s.
- Aggressive vendor styles, but publisher styles enabled – Very little is seen of the publisher styles in this scenario. They mainly surface in edge cases that weren’t accounted for in the vendor’s stylesheet.
- Minimal overrides – The vendor only really enforces control over margins, backgrounds, and possibly font styles.
- Publisher styles – The mode that the reading app goes into when the reader deliberately selects ‘publisher styles’. Under ordinary circumstances this would simply disable the overrides but in most reading apps this mode has a unique behaviour.