Bypassing AppProtocol Prompts

This article is a repost promoting content originally published elsewhere. See more things Dan's reposted.

Starting in Edge 82.0.425.0 Canary, a new flag is available.

Edge Canary showing an "Always allow [this website] to open links of this type..." checkbox

This is a good move; a relatively simple innovation that’s sure to help end-user security. If you can’t see what’s different above without following the link through to the original article, here’s the short version: an upcoming version of Edge will allow you to authorise a specific site to open a particular application to handle a link… without having to compromise by choosing either to (a) see the security dialog every single time (which teaches users to “just click OK”) or (b) allow the dialog to be suppressed for links that open a particular application (which makes it easier for bad guys to make poisonous links).

So you’ll be able to, for example, say “slack.com can open Slack for me, but other websites have to ask”. Nice.

I hope that other browser manufacturers follow suit, especially on mobile where the web/web-launched-native-app boundary has never been fuzzier.

Edge Canary showing an "Always allow [this website] to open links of this type..." checkbox×

Edge Blink and Progressive Web Apps

As I’ve previously mentioned (sadly), Microsoft Edge is to drop its own rendering engine EdgeHTML and replace it with Blink, Google’s one (more of my and others related sadness here, here, here, and here). Earlier this month, Microsoft made available the first prerelease versions of the browser, and I gave it a go.

Edge Canary 75.0.131.0 dev
At a glance, it looks exactly like you’d expect a Microsoft reskin of Chrome to look, right down to the harmonised version numbers.

All of the Chrome-like features you’d expect are there, including support for Chrome plugins, but Microsoft have also clearly worked to try to integrate as much as possible of the important features that they felt were distinct to Edge in there, too. For example, Edge Blink supports SmartScreen filtering and uses Microsoft accounts for sync, and Incognito is of course rebranded InPrivate.

But what really interested me was the approach that Edge Dev has taken with Progressive Web Apps.

Installing NonStopHammerTi.me as a standalone PWA in Edge
NonStopHammerTi.me might not be the best PWA in the world, but it’s the best one linked from this blog post.

Edge Dev may go further than any other mainstream browser in its efforts to make Progressive Web Apps visible to the user, putting a plus sign (and sometimes an extended install prompt) right in the address bar, rather than burying it deep in a menu. Once installed, Edge PWAs “just work” in exactly the way that PWAs ought to, providing a simple and powerful user experience. Unlike some browsers, which make installing PWAs on mobile devices far easier than on desktops, presumably in a misguided belief in the importance of mobile “app culture”, it doesn’t discriminate against desktop users. It’s a slick and simple user experience all over.

NonStopHammerTi.me running as a standalone PWA in Edge Dev.
Once installed, Edge immediately runs your new app (closing the tab it formerly occupied) and adds shortcut icons.

Feature support is stronger than it is for Progressive Web Apps delivered as standalone apps via the Windows Store, too, with the engine not falling over at the first sign of a modal dialog for example. Hopefully (as I support one of these hybrid apps!) these too will begin to be handled properly when Edge Dev eventually achieves mainstream availability.

Edge provides an option to open a page in its sites' associated PWA, if installed.
If you’ve got the “app” version installed, Edge provides a menu option to switch to that from any page on the conventional site (and cookies/state is retained across both).

But perhaps most-impressive is Edge Dev’s respect for the importance of URLs. If, having installed the progressive “app” version of a site you subsequently revisit any address within its scope, you can switch to the app version via a link in the menu. I’d rather have seen a nudge in the address bar, where the user might expect to see such things (based on that being where the original install icon was), but this is still a great feature… especially given that cookies and other state maintainers are shared between the browser, meaning that performing such a switch in a properly-made application will result in the user carrying on from almost exactly where they left off.

An Edge PWA showing its "Copy URL" feature.
Unlike virtually every other PWA engine, Edge Dev’s provides a “Copy URL” feature even to apps without address bars, which is a killer feature for sharability.

Similarly, and also uncommonly forward-thinking, Progressive Web Apps installed as standalone applications from Edge Dev enjoy a “copy URL” option in their menu, even if the app runs without an address bar (e.g. as a result of a "display": "standalone" directive in the manifest.json). This is a huge boost to sharability and is enormously (and unusually) respectful of the fact that addresses are the Web’s killer feature!  Furthermore, it respects the users’ choice to operate their “apps” in whatever way suits them best: in a browser (even a competing browser!), on their mobile device, or wherever. Well done, Microsoft!

I’m still very sad overall that Edge is becoming part of the Chromium family of browsers. But if the silver lining is that we get a pioneering and powerful new Progressive Web App engine then it can’t be all bad, can it?

Edge Canary 75.0.131.0 dev× Installing NonStopHammerTi.me as a standalone PWA in Edge× NonStopHammerTi.me running as a standalone PWA in Edge Dev.× Edge provides an option to open a page in its sites' associated PWA, if installed.× An Edge PWA showing its "Copy URL" feature.×

Chromedge and headcount

This article is a repost promoting content originally published elsewhere. See more things Dan's reposted.

So Microsoft is going to retire EdgeHTML and use Chromium instead for Edge while not really answering the question if the web [is] better off with less engine diversity. This upset people, and Mozilla, especially, is worrying about the future:

Will Microsoft’s decision make it harder for Firefox to prosper? It could. Making Google more powerful is risky on many fronts. […] If one product like Chromium has enough market share, then it becomes easier for web developers and businesses to decide not to worry if their services and sites work with anything other than Chromium. That’s what happened when Microsoft had a monopoly on browsers in the early 2000s before Firefox was released. And it could happen again.

Before you lament the return to a Microsoft-like monopoly, remember what happened to Microsoft’s monopoly. In fact, remember what happened to the lineal descendant of that monopoly just last week. Near-monopolies do not necessarily mean the end of the web.

Yet more in the “EdgeHTML to be replaced by Chromium” story, on which I already shared my opinions. Peter-Paul does a good job of illustrating the differences between the reduction of diversity in/increasing monopolisation of the browser space this time around and last time (when Internet Explorer 6 became the de facto standard way to surf the Web), using it to provide a slightly less-pessimistic outlook (albeit one not without its warnings).

Browser diversity starts with us

This article is a repost promoting content originally published elsewhere. See more things Dan's reposted.

Jeffrey Zeldman (zeldman.com)

Even if you love Chrome, adore Gmail, and live in Google Docs or Analytics, no single company, let alone a user-tracking advertising giant, should control the internet.

Diversity is as good for the web as it is for society. And it starts with us.

Yet more fallout from the Microsoft announcement that Edge will switch to Chromium, which I discussed earlier. This one’s pretty inspirational, and gives a good reminder about what our responsibilities are to the Web, as its developers.

Edge may be becoming Chromium-powered, and that’s terrible

Microsoft engineers have been spotted committing code to Chromium, the backend of Google Chrome and many other web browsers. This, among other things, has lead to speculation that Microsoft’s browser, Edge, might be planned to switch from its current rendering engine (EdgeHTML) to Blink (Chromium’s). This is bad news.

This page in Microsoft Edge
This post, as it would appear if you were looking at it in Edge. Which you might be, I suppose.

The younger generation of web developers are likely to hail this as good news: one fewer engine to develop for and test in, they’re all already using Chrome or something similar (and certainly not Edge) for development and debugging anyway, etc. The problem comes perhaps because they’re too young to remember the First Browser War and its aftermath. Let me summarise:

  1. Once upon a time – let’s call it the mid-1990s – there were several web browsers: Netscape Navigator, Internet Explorer, Opera, etc. They all used different rendering engines and so development was sometimes a bit of a pain, but only if you wanted to use the latest most cutting-edge features: if you were happy with the standard, established features of the Web then your site would work anywhere, as has always been the case.
    Best viewed with... any damn browser
  2. Then, everybody starting using just one browser: following some shady dealings and monopoly abuse, 90%+ of Web users started using just one web browser, Internet Explorer. By the time anybody took notice, their rivals had been economically crippled beyond any reasonable chance of recovery, but the worst had yet to come…
    Best viewed with Internet Explorer
  3. Developers started targeting only that one browser: instead of making websites, developers started making “Internet Explorer sites” which were only tested in that one browser or, worse yet, only worked at all in that browser, actively undermining the Web’s position as an open platform. As the grip of the monopoly grew tighter, technological innovation was centred around this single platform, leading to decade-long knock-on effects.
  4. The Web ceased to grow new features: from the release of Internet Explorer 6 there were no significant developments in the technology of the Web for many years. The lack of competition pushed us into a period of stagnation. A decade and a half later, we’re only just (finally) finishing shaking off this unpleasant bit of our history.
    "Netscape sux"

History looks set to repeat itself. Substitute Chrome in place of Internet Explorer and update the references to other web browsers and the steps above could be our future history, too. Right now, we’re somewhere in or around step #2 – Chrome is the dominant browser – and we’re starting to see the beginnings of step #3: more and more “Chrome only” sites. More-alarmingly this time around, Google’s position in providing many major Web services allows them to “push” even harder for this kind of change, even just subtly: if you make the switch from Chrome to e.g. Firefox (and you absolutely should) you might find that YouTube runs slower for you because YouTube’s (Google) engineers favour Google’s web browser.

Chrome is becoming the new Internet Explorer 6, and that’s a huge problem. Rachel Nabors wrote in her excellent article The Ecological Impact of Browser Diversity:

So these are the three browser engines we have: WebKit/Blink, Gecko, and EdgeHTML. We are unlikely to get any brand new bloodlines in the foreseeable future. This is it.

If we lose one of those browser engines, we lose its lineage, every permutation of that engine that would follow, and the unique takes on the Web it could allow for.

And it’s not likely to be replaced.

The Circle of Browsers, by Rachel Nabors

Imagine a planet populated only by hummingbirds, dolphins, and horses. Say all the dolphins died out. In the far, far future, hummingbirds or horses could evolve into something that could swim in the ocean like a dolphin. Indeed, ichthyosaurs in the era of dinosaurs looked much like dolphins. But that creature would be very different from a true dolphin: even ichthyosaurs never developed echolocation. We would wait a very long time (possibly forever) for a bloodline to evolve the traits we already have present in other bloodlines today. So, why is it ok to stand by or even encourage the extinction of one of these valuable, unique lineages?

We have already lost one.

We used to have four major rendering engines, but Opera halted development of its own rendering engine Presto before adopting Blink.

Three left. Spend them wisely.

As much as I don’t like having to work-around the quirks in all of the different browsers I test in, daily, it’s way preferable to a return to the dark days of the Web circa most of the first decade of this century. Please help keep browsers diverse: nobody wants to start seeing this shit –

Best viewed with Google Chrome

Update: this is now confirmed. A sad day for the Web.

This page in Microsoft Edge× Best viewed with Google Chrome×

How Edge Follows In IE’s Security Failings

I’ve generally been pretty defensive of Microsoft Edge, the default web browser in Windows 10. Unlike its much-mocked predecessor Internet Explorer, Edge is fast, clean, modern, and boasts good standards-compliance: all of the things that Internet Explorer infamously failed at! I was genuinely surprised to see Edge fail to gain a significant market share in its first few years: it seemed to me that everyday Windows users installed other browsers (mostly Chrome, which is causing its own problems) specifically because Internet Explorer was so terrible, and that once their default browser was replaced with something moderately-good this would no longer be the case. But that’s not what’s happened. Maybe it’s because Edge’s branding is too-remiscient of its terrible predecessor or maybe just because Windows users have grown culturally-used to the idea that the first thing they should do on a new PC is download a different browser, but whatever the reason, Edge is neglected. And for the most part, I’ve argued, that’s a shame.

Edge's minimalistic Certificate View.
I ranted at an Edge developer I met at a conference, once, about Edge’s weak TLS debugging tools that couldn’t identify an OCSP stapling issue that only affected Edge, but I thought that was the worse of its bugs… until now…

But I’ve changed my tune this week after doing some research that demonstrates that a long-standing security issue of Internet Explorer is alive and well in Edge. This particular issue, billed as a “feature” by Microsoft, is deliberately absent from virtually every other web browser.

About 5 years ago, Steve Gibson observed a special feature of EV (Extended Validation) SSL certificates used on HTTPS websites: that their extra-special “green bar”/company name feature only appears if the root CA (certificate authority) is among the browser’s default trust store for EV certificate signing. That’s a pretty-cool feature! It means that if you’re on a website where you’d expect to see a “green bar”, like Three Rings, PayPal, or HSBC, then if you don’t see the green bar one day it most-likely means that your connection is being intercepted in the kind of way I described earlier this year, and everything you see or send including passwords and credit card numbers could be at risk. This could be malicious software (or nonmalicious software: some antivirus software breaks EV certificates!) or it could be your friendly local network admin’s middlebox (you trust your IT team, right?), but either way: at least you have a chance of noticing, right?

Firefox address bars showing EV certificates of Three Rings CIC (GB), PayPal, Inc. (US), and HSBC Holdings plc (GB)
Firefox, like most browsers, shows the company name in the address bar when valid EV certificates are presented, and hides it when the validity of that certificate is put into question by e.g. network sniffing tools set up by your IT department.

Browsers requiring that the EV certificate be signed by a one of a trusted list of CAs and not allowing that list to be manipulated (short of recompiling the browser from scratch) is a great feature that – were it properly publicised and supported by good user interface design, which it isn’t – would go a long way to protecting web users from unwanted surveillance by network administrators working for their employers, Internet service providers, and governments. Great! Except Internet Explorer went and fucked it up. As Gibson reported, not only does Internet Explorer ignore the rule of not allowing administrators to override the contents of the trusted list but Microsoft even provides a tool to help them do it!

Address bars from major browsers connecting to a spoofed site, with EV certificate "green bars" showing only in Internet Explorer and Edge.
From top to bottom: Internet Explorer 11, Edge 17, Firefox 61, Chrome 68. Only Internet Explorer and Edge show the (illegitimate) certificate for “Barclays PLC”. Sorry, Barclays; I had to spoof somebody.

I decided to replicate Gibson’s experiment to confirm his results with today’s browsers: I was also interested to see whether Edge had resolved this problem in Internet Explorer. My full code and configuration can be found here. As is doubtless clear from the title of this post and the screenshot above, Edge failed the test: it exhibits exactly the same troubling behaviour as Internet Explorer.

Thanks, Microsoft.

Safari doesn't fall for it, either.
I also tried Safari (both on MacOS, above, and iOS, below) and it behaved as the other non-Microsoft browsers do (i.e. arguably more-correctly than IE or Edge).

I shan’t for a moment pretend that our current certification model isn’t without it’s problems – it’s deeply flawed; more on that in a future post – but that doesn’t give anybody an excuse to get away with making it worse. When it became apparent that Internet Explorer was affected by the “feature” described above, we all collectively rolled our eyes because we didn’t expect better of everybody’s least-favourite web browser. But for Edge to inherit this deliberate-fault, despite every other browser (even those that share its certificate store) going in the opposite direction, is just insulting.

Edge's minimalistic Certificate View.× Firefox address bars showing EV certificates of Three Rings CIC (GB), PayPal, Inc. (US), and HSBC Holdings plc (GB)× Address bars from major browsers connecting to a spoofed site, with EV certificate "green bars" showing only in Internet Explorer and Edge.× Safari doesn't fall for it, either.×