The 95th percentile of RUM data is a great place to assess the slowest experiences. In this case, we see that the streaming Service Worker confers a 40% and 51% improvement in FCP and LCP, respectively, over no Service Worker at all. Compared to the “standard” Service Worker, we see a reduction in FCP and LCP by 19% and 43%, respectively.
What a fantastic article from Jess Peck on Cumulative Layout Shift. It’s approachable to folks new to the metric, detailed and in-depth and wildly entertaining (more entertaining than a post this informative has any right to be).
An in-depth, well researched guide to measuring Core Web Vitals from Barry (par for the course for him).
I love it when someone takes a specific problem (in this case, adding text labels to buttons in an accessible way, and then digs deep into solving it.
This is a terrific post by Sara, where she dives into making “Add to Cart” (and other generic text labels) more accessible to both screen readers and dictation services.
Huh. So Stefan’s today I learned is now my today I learned. Apparently links have a ping attribute that you can tell the browser to send a POST request to when a link is clicked.
Again, if you’re certain that you’re speaking to peers, that’s fine. But if you’re trying to communicate even a little more widely, then initialisms and abbreviations are obstacles to overcome. And once you’re in the habit of using the short forms, it gets harder and harder to apply context-shifting in your language. So the safest habit to form is to generally avoid using acronyms and initialisms.
This is a good reminder from Jeremy. He mentions performance in particular (we do love our acronyms). I try to avoid this, but I know I’ve been guilty of it many times. Something to improve on for sur.
A smart little list of optimizations for loading images efficiently. Using the bytes if the image as a hash for automatic cache busting if the image changes is particularly clever.
Alex posted a follow-up to a prior post on avoiding scrollbar jumping when using content-visibility.
It’s clever stuff—the combination of ResizeObservers and IntersectionObservers helping to avoid the shifting around that would occur otherwise.
This doesn’t do much though to eliminate the reservations I have about content-visibility. In theory, it’s a great addition, but the fact that it seems to need so much supporting scaffolding to make it usable for a relatively simple use-case makes me feel like it may be missing a few other pieces of native plumbing before it’s really ready for primetime.
Sad, but true words:
For a few months, those who will buy M1 machines will enjoy great responsiveness and blazing start-up time. Some once bloated applications will again behave like most tools should. But soon these metrics will start to degrade. Responsiveness and start-up time will progressively revert to what they used to be and old “non-M1” machines will become even slower than they used to.
For every cycle a hardware engineer saves, a software engineer will add two instructions.
Imagine that situation. You buy a computer. It comes with one web browser pre-installed. You can’t install a different web browser on your computer.
You wouldn’t stand for it! I mean, Microsoft got fined for anti-competitive behaviour when they pre-bundled their web browser with Windows back in the 90s. You could still install other browsers, but just the act of pre-bundling was seen as an abuse of power. Imagine if Windows never allowed you to install Netscape Navigator?
And yet that’s exactly the situation in 2020.
You buy a computing device from Apple. It might be a Macbook. It might be an iPad. It might be an iPhone. But you can only install your choice of web browser on one of those devices.