One of the principles behind HTML5, and the community building it, is that the specifications that say how the Web works should have enough detail that somebody reading them can implement the specification. This makes it easier for new Web browsers to enter the market, which in turn helps users through competitive pressure on existing and new browsers.

I worry that the Web standards community is in danger of losing this principle, quite quickly, and at a cost to competition on the Web.

Some of the recent threats to the ability to implement competitive browsers are non-technical:

• Many leading video and audio codecs are subject to non-free patent licenses, due at least in part to the patent policies and practices of the standards bodies building such codecs.
• Implementing EME in a way that is usable in practice requires having a proprietary DRM component and then convincing the sites that use EME to support that component. This can be done by building such a component or forming a business relationship with somebody else who already has. But this threat to browser competition is at least partly related to the nature of DRM, whose threat model treats the end user as the attacker.

Many parts of the technology industry today are dominated by a small group of large companies (effectively an oligopoly) that have an ecosystem of separate products that work better together than with their competitors' products. Apple has Mac OS (software and hardware), iOS (again, software and hardware), Apple TV, Apple Pay, etc. Google has its search engine and other Web products, Android (software only), Chrome OS, Chromecast and Google Cast, Android Pay, etc. Microsoft has Windows, Bing, Windows Phone, etc. These products don't line up precisely, but they cover many of the same areas while varying based on the companies strengths and business models. Many of these products are tied together in ways that both help users and, since these ties aren't standardized and interoperable, strongly encourage users to use other products from the same company.

There are some Web technologies in development that deal with connections between parts of these ecosystems. For example:

• The Presentation API defines a way for a Web page to show content on something like a Chromecast or an Apple TV. But it only specifies the API between the Web page and the browser; the API between the browser and the TV is completely unspecified. (Mozilla participants in the group tried to change that early in the group's history, but gave up.)
• The future Web Payments Working Group (which I wrote about last week) is intended to build technology in which the browser connects a user making a payment to a Web site. This has the risk that instead of specifying how browsers talk to payment networks or banks, a browser is expected to make business deals with them, or make business deals with somebody who already has such deals.

In both cases, specifying the system fully is more work. But it's work that needs to happen to keep the Web open and competitive. That's why we've had the principle of complete specification, and it still applies here.

I'm worried that the ties that connect the parts of these ecosystems together will start running through unspecified parts of Web technologies. This would, through the loss of the principle of specification for competition, makes it harder for new browsers (or existing browsers made by smaller companies) to compete, and would make the Web as a whole a less competitive place.