I think it’d be neat if there was a standard that allowed browser engines to move forward with breaking changes (or any changes) under the concept of “versions”.
Websites could specify which version of features they use. Engines could by default ship with the latest version. If a website is using an older version of features, then the browser prompts the user to install those older features.
This could allow, for example, things like the problematic new EcmaScript class fields to be fixed in a way that newer websites could specify that they use that version of the engine, while older browser continue to use a previous version.
The only thing back-ported to older versions are security fixes (and bug fixes if vendors care enough).
How would that look like? Maybe a root-level entry in
manifest.json or something could specify a
webVersion field, or something.
As specs move forward, a snapshot of all the specs is created at some version number. This includes the spec’d state for HTML, CSS, DOM, EcmaScript, etc.
This would help to reduce the size of browser engines while bringing the web forward. Eventually, hen old websites are no longer visited and old features are no longer used, the average user will not download that version of the engine. They’ll only by default have the latest version with latest features, and sometimes they’ll need to accept a version download for websites still using older versions.
Perhaps a browser would ship with the most common versions still in use. There’d be some statistical threshold for determining which versions to ship with by default. Etc.
New versions doesn’t mean removing old features (though it might). A new versions might remove bad features of the web, or only make some fixes to bad parts.
A main downside of this would be that more code has to be maintained by vendors.
Anyway, I am dreaming of a better landscape.