What is the Value of Browser Diversity?

In May 2019 I attended a talk by Mike Taylor who works on webcompat at Mozilla. Mike told the sordid story of window.event, a non-standard IE invention that was replicated in Konqueror, which showed up in Webkit, which stuck around in Blink, and was now Mike’s problem in Firefox. It was a good story fraught with ups and downs and literal “Breaking the Web” level changes for a tiny feature rollout.

At the end of the talk Mike threw out a pretty prescient question (Edge had just released its Chromium beta) and I’ve been mulling over it ever since:

What is the value of browser diversity? If Firefox switched to Chromium tomorrow, what would we lose?

– Mike Taylor, a traitor (apparently)

Mike made it clear that the question was purely theoretical and no serious talk about this was happening at Mozilla at the time. Nonetheless, it was a challenging thought. Throwing away all sunk costs, what is the value of the colossal expense required to employ engineering teams to chase Chrome’s tail?

I’ve thought about these questions for over a year and narrowed my feelings of browser diversity down to two major value propositions:

1. Browser diversity keeps the Web deliberately slow
2. Browser diversity fosters consensus and cooperation over corporate rule

They are similar, but slightly different concepts for me.

Slow, like brisket.

I think the Web platform’s most frustrating aspect is also its greatest asset: it’s slow. It’s not just slow, it’s “it took 10 years to ship the <main> element which is just a spicy <div>” kind of slow. It’s glacial.

This can be agonizing while you wait for a much needed feature to roll out in all browsers, only to find out five years in the process one browser refuses the entire premise of the feature (RIP HTML Imports). The big tradeoff is that web platform features have to run the gauntlet and more thinking is applied over time: robustness, naming, internationalization, accessibility, security, etc. all have proper time for consideration and aren’t rushed through like it’s a product sprint.

[…]

Cooperation, not corporation.

Browser diversity means browser vendors are hindered from shipping features that only benefit themselves (e.g. ActiveX in IE, -webkit-box-reflect, etc). Good ideas have to be open and meet a pseudo-requirement of ubiquitous utility. To make good platform features requires consensus, not competition, and the web’s potential is born out of cooperation, not a single corporation.

It’s hard to quantify this, but if all aspects of the Web (development, browsing, searching, hosting) are ceded to a single corporation, all it takes is one heavy-handed manager or executive hellbent on hitting some OKRs to push their thumb on the scale of the Web. If the Web is governed by a single corporation, it will start looking like that corporation’s vision of the Web, ultimately limiting its own potential. Trading short term gain on new shiny features for long term vision.