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When I copy a browser tab URL, I often want to also keep the title. Sometimes I want to use the link as rich text (e.g., when pasting the link into OneNote or Jira). Sometimes I prefer a Markdown link. There are browser extensions to achieve this task, but I don't want to introduce potential security issues. Instead, I've written a bookmarklet based on this example extension. To use it, drag the following link onto your browser bookmarks bar: Copy Tab When you click the bookmark(let), the current page including its title will be copied into your clipboard. You don't even have to choose the output format: the link is copied both as rich text and plain text (Markdown). This works because it's possible to write multiple values into the clipboard with different content types. Here's the source code: function escapeHTML(str) { return String(str) .replace(/&/g, "&") .replace(/"/g, """) .replace(/'/g, "'") .replace(/</g, "<") .replace(/>/g, ">"); } function copyToClipboard({ url, title }) { function onCopy(event) { document.removeEventListener("copy", onCopy, true); // hide the event from the page to prevent tampering event.stopImmediatePropagation(); event.preventDefault(); const linkAsMarkdown = `[${title}](${url})`; event.clipboardData.setData("text/plain", linkAsMarkdown); const linkAsHtml = `<a href="${escapeHTML(url)}">${title}</a>` event.clipboardData.setData("text/html", linkAsHtml); } document.addEventListener("copy", onCopy, true); document.execCommand("copy"); } copyToClipboard({ url: window.location.toString(), title: document.title });
While redesigning my photography website, I've looked into the Open Graph (OG) images, which are displayed when sharing a link on social media or messaging apps. Here's an example from WhatsApp: For each photo that I publish, I create a WebP thumbnail for the gallery. I wanted to use those as OG images, but the WebP support was lacking, so I've been creating an additional JPG variant just for Open Graph. I was interested in seeing how things have changed in the last 2.5 years. I've tested the following platforms: WhatsApp, Telegram, Signal, Discord, Slack, Teams, Facebook, LinkedIn, Xing, Bluesky, Threads and Phanpy (Mastodon). Here are the results: All providers support JPEG and PNG. All providers except Teams and Xing support WebP. No provider except Facebook supports AVIF. WhatsApp displays the AVIF image, but the colors are broken. "X, formerly Twitter" didn't display OG images for my test pages at all. I don't care about that platform, so I didn't bother to further investigate. Those results confirmed that I could now use WebP Open Graph images without creating an additional JPG file.
I'm a frequent user of bookmarklets. As I'm sharing some of them on my blog, I wrote this post to explain what bookmarklets are and how to use them. In short, a bookmarklet is a browser bookmark containing JavaScript code. Clicking the bookmark executes the script in the context of the current web page, allowing users to perform tasks such as modifying the appearance of a webpage or extracting information. Bookmarklets are a simpler, more lightweight alternative to browser extensions, Chrome snippets, and userscripts. How to add a bookmarklet? Here's an example to display a browser dialog with the title of the current web page: Display page title You can click the link to see what it does. To run this script on other websites, we have to save it as a bookmarklet. My preferred way is to drag the link onto the bookmarks toolbar: A link on a web page is dragged and dropped onto a browser bookmark bar. A bookmark creation dialog appears. The prompt is confirmed and closed. The created bookmarklet is clicked. The current web page title is displayed in a browser dialog. Another way is to right-click the link to open its context menu: In Firefox, you can then select "Bookmark Link…". Other browsers make it a little more difficult: select "Copy Link (Address)", manually create a new bookmark, and then paste the copied URL as the link target. Once created, you can click the bookmark(let) on any web page to display its title. Scroll further down to see more useful use cases. How to write a bookmarklet? Let's start with the code for the previous bookmarklet example: window.alert(document.title) To turn that script into a bookmarklet, we have to put javascript: in front of it: javascript:window.alert(document.title) To keep our code self-contained, we should wrap it with an IIFE (immediately invoked function expression): javascript:(() => { window.alert(document.title) })() Finally, you might have to URL-encode your bookmarklet if you get issues with special characters: javascript:%28%28%29%20%3D%3E%20%7B%0A%20%20window.alert%28document.title%29%0A%7D%29%28%29 Useful bookmarklets Here are some bookmarklets I've created: Debugger — Starts the browser DevTools debugger after 3 seconds, useful for debugging dynamic content changes. Log Focus Changes — Logs DOM elements when the focus changes. Design Mode — Makes the web page content-editable (toggle).
It can be frustrating to fill out a web form, only to accidentally refresh the page (or click "back") and lose all the hard work. In this blog post, I present a method to retain form data when the page is reloaded, which improves the user experience. Browser behavior Most browsers provide an autofill feature. In the example form below, enter anything into the input field. Then, try out the following: Click the "Example link" and use the "back" functionality of your browser. Reload the page. Query Example link Depending on your browser, the input value might be restored: Browser Reload Back Firefox 130 Yes Yes Chrome 129 No Yes Safari 18 No Yes How does it work? I was surprised to learn that this autofill behavior is controlled via the autocomplete, that is mostly used for value autocompletion from past web forms. However, if we disable the autocompletion, the autofill feature will be disabled as well: <input autocomplete="false" /> To learn more about the behavior, read the full spec on persisted history entry state. Preserving application state Even with autofill, no browser will restore dynamic changes previously triggered by the user. In the following example, the user has to always press the "Search" button to view the results: This is an interactive example. Please enable JavaScript to use it. Query Search ... const inputElementNative = document.querySelector("#example-search-input"); const outputElementNative = document.querySelector("#example-search-output"); const performSearch_exampleSearch = (outputElement) => { outputElement.innerText = ""; const introText = document.createTextNode("Open the result for "); outputElement.appendChild(introText); const link = document.createElement("a"); link.href = "https://example.com"; link.innerText = inputElementNative.value || "no text"; outputElement.appendChild(link); }; document.querySelector("#example-search-form").addEventListener("submit", (event) => { event.preventDefault(); performSearch_exampleSearch(outputElementNative); }, ); If the web page changes its content after user interaction, it might be a good idea to restore the UI state after the page has been refreshed. For example, it's useful to restore previous search results for an on-site search. Note that Chrome will fire a change event on inputs, but this is considered a bug as the respective spec has been updated. Storing form values As the form value might be lost on reload, we need to store it temporarily. Some common places to store data include local storage, session storage, cookies, query parameters or hash. They all come with drawbacks for our use case, though. Instead, I suggest using the browser history state, which has several advantages: We get data separation between multiple browser tabs with no additional effort. The data is automatically cleaned up when the browser tab is closed. We don't pollute the URL and prevent page reloads. Let's store the search input value as query: document.querySelector("form").addEventListener("submit", (event) => { event.preventDefault(); const inputElement = document.querySelector("input"); history.replaceState({ query: inputElement.value }, ""); performSearch(); }); This example uses the submit event to store the data, which fits our "search" use case. In a regular form, using the input change event might be a better trigger to store form values. Using replaceState over pushState will ensure that no unnecessary history entry is created. Uncaught TypeError: Failed to execute 'replaceState' on 'History': 2 arguments required, but only 1 present. Restoring form values My first approach to restore form values was to listen to the pageshow event. Once it's fired, we can access the page load type from window.performance: window.addEventListener("pageshow", () => { const type = window.performance.getEntriesByType("navigation")[0].type; const query = history.state?.query; if (query && (type === "back_forward" || type === "reload")) { document.querySelector("#my-input").value = query; performSearch(); } }); I will keep the solution here in case someone needs it, but usually it is unnecessary to check the page load type. Because the history state is only set after the search form has been submitted, we can check the state directly: const query = history.state?.query; if (query) { document.querySelector("#my-input").value = query; performSearch(); } Demo Here's an example combining both techniques to store and restore the input value: This is an interactive example. Please enable JavaScript to use it. Query Search ... const inputElementCustom = document.querySelector("#example-preserve-input"); const outputElementCustom = document.querySelector("#example-preserve-output"); const performSearch_examplePreserve = (outputElement) => { outputElement.innerText = ""; const introText = document.createTextNode("Open the result for "); outputElement.appendChild(introText); const link = document.createElement("a"); link.href = "https://example.com"; link.innerText = inputElementCustom.value || "no text"; outputElement.appendChild(link); }; document.querySelector("#example-preserve-form").addEventListener("submit", (event) => { event.preventDefault(); performSearch_examplePreserve(outputElementCustom); history.replaceState({ query: inputElementCustom.value }, ""); }); const historyQuery = history.state?.query; if (historyQuery) { document.querySelector("#example-preserve-input").value = historyQuery; performSearch_examplePreserve(outputElementCustom); } Conclusion Preserving form data on page refresh is a small but impactful way to improve user satisfaction. The default browser autofill feature handles only basic use cases, so ideally we should maintain the form state ourselves. In this blog post, I've explained how to use the browser history state to temporarily store and retrieve form values.
In this post, I will summarize some problems and constraints that I've encountered with the Notifications and Push web APIs. Notification settings on macOS Someone who's definitely not me wasted half an hour wondering why triggered notifications would not appear. On macOS, make sure to enable system notifications for your browsers. Open "System Settings" → "Notifications". For each browser, select "Allow notifications" and set the appearance to "Alerts": Onchange listener not called Web APIs offer a way to subscribe to change events. This is especially useful in React: navigator.permissions .query({ name: "push", userVisibleOnly: true }) .then((status) => { status.onchange = function () { // synchronize permission status with local state setNotificationPermission(this.state); }; }); Whenever the notification permission changes (either through our application logic or via browser controls), we can synchronize the UI in real-time according to the current permission value (prompt, denied or granted). However, due to a Firefox bug, the event listener callback is never called. This means that we can't react to permission changes via browser controls in Firefox. That's especially unfortunate when combined with push messages, where we want to subscribe the user once they grant the notification permission. One workaround is to check at page load if the notification permission is granted with no valid subscription and resubscribe the user. Notification image not supported Browser notifications support an optional image property. This property is marked as "experimental", so it's not surprising that some browsers (Firefox, Safari) don't support it. There is an open feature request to add support in Firefox, but it has been open since 2019. VAPID contact information required When sending a push message, we have to provide VAPID parameters (e.g. the public and private key). According to the specification, the sub property (contact email or link) is optional: If the application server wishes to provide, the JWT MAY include a "sub" (Subject) claim. Despite this specification, the Mozilla push message server will return an error if the subject is missing: 401 Unauthorized for (...) and subscription https://updates.push.services.mozilla.com/wpush/v2/… You might not encounter this issue when using the popular web-push npm package, as its API encourages you to provide the subject as the first parameter: webpush.setVapidDetails("hello@example.com", publicKey, privateKey); However, in the webpush-java library, you need to set the subject explicitly: builder.subject("hello@example.com"); There is an open issue with more information about this problem. Microsoft Edge pitfalls Microsoft introduced adaptive notification requests in the Edge browser. It is a crowdsourced score system, which may auto-accept or auto-reject notification requests. The behavior can be changed in the Edge notification settings. Additionally, on a business or school device, those settings might be fixed, displaying the following tooltip: This setting is managed by your organization.
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Here’s Jony Ive talking to Patrick Collison about measurement and numbers: People generally want to talk about product attributes that you can measure easily with a number…schedule, costs, speed, weight, anything where you can generally agree that six is a bigger number than two He says he used to get mad at how often people around him focused on the numbers of the work over other attributes of the work. But after giving it more thought, he now has a more generous interpretation of why we do this: because we want relate to each other, understand each other, and be inclusive of one another. There are many things we can’t agree on, but it’s likely we can agree that six is bigger than two. And so in this capacity, numbers become a tool for communicating with each other, albeit a kind of least common denominator — e.g. “I don’t agree with you at all, but I can’t argue that 134 is bigger than 87.” This is conducive to a culture where we spend all our time talking about attributes we can easily measure (because then we can easily communicate and work together) and results in a belief that the only things that matter are those which can be measured. People will give lip service to that not being the case, e.g. “We know there are things that can’t be measured that are important.” But the reality ends up being: only that which can be assigned a number gets managed, and that which gets managed is imbued with importance because it is allotted our time, attention, and care. This reminds me of the story of the judgement of King Solomon, an archetypal story found in cultures around the world. Here’s the story as summarized on Wikipedia: Solomon ruled between two women who both claimed to be the mother of a child. Solomon ordered the baby be cut in half, with each woman to receive one half. The first woman accepted the compromise as fair, but the second begged Solomon to give the baby to her rival, preferring the baby to live, even without her. Solomon ordered the baby given to the second woman, as her love was selfless, as opposed to the first woman's selfish disregard for the baby's actual well-being In an attempt to resolve the friction between two individuals, an appeal was made to numbers as an arbiter. We can’t agree on who the mother is, so let’s make it a numbers problem. Reduce the baby to a number and we can agree! But that doesn’t work very well, does it? I think there is a level of existence where measurement and numbers are a sound guide, where two and two make four and two halves make a whole. But, as humans, there is another level of existence where mathematical propositions don’t translate. A baby is not a quantity. A baby is an entity. Take a whole baby and divide it up by a sword and you do not half two halves of a baby. I am not a number. I’m an individual. Indivisible. What does this all have to do with software? Software is for us as humans, as individuals, and because of that I believe there is an aspect of its nature where metrics can’t take you.cIn fact, not only will numbers not guide you, they may actually misguide you. I think Robin Rendle articulated this well in his piece “Trust the vibes”: [numbers] are not representative of human experience or human behavior and can’t tell you anything about beauty or harmony or how to be funny or what to do next and then how to do it. Wisdom is knowing when to use numbers and when to use something else. Email · Mastodon · Bluesky
When I drive the 24 Hours of Le Mans, I spend a total of about 6-9 hours in the car, divided into stints of roughly two hours at a time. It's intense. But talking with Lex Fridman in Austin on his podcast? Over six hours straight! We only interrupted the session for five minutes total to take three bathroom breaks. All that endurance training has clearly paid off! But the magic of a good conversation, like the magic of driving at Le Mans, is that time flies by. Those six hours felt more like sixty minutes. This is what flow does: it compresses the moment. Besides, we had plenty to talk about. Lex prepares like no other podcast I've ever been on. Pages and pages of notes. Deep questions, endless attention for tangents. We covered the beauty of Ruby for half an hour alone! But also the future of AI, small teams, why we left the cloud, Elon Musk, fatherhood, money and happiness, and a million other topics (which Lex mercifully timestamps, so listeners without six hours to spare can hop around). It was a privilege to appear. If you're interested, the conversation is on YouTube, on Spotify, on X, and as a regular podcast.
Exploring diagram.website, I came across The Computer is a Feeling by Tim Hwang and Omar Rizwan: the modern internet exerts a tyranny over our imagination. The internet and its commercial power has sculpted the computer-device. It's become the terrain of flat, uniform, common platforms and protocols, not eccentric, local, idiosyncratic ones. Before computers were connected together, they were primarily personal. Once connected, they became primarily social. The purpose of the computer shifted to become social over personal. The triumph of the internet has also impoverished our sense of computers as a tool for private exploration rather than public expression. The pre-network computer has no utility except as a kind of personal notebook, the post-network computer demotes this to a secondary purpose. Smartphones are indisputably the personal computer. And yet, while being so intimately personal, they’re also the largest distribution of behavior-modification devices the world has ever seen. We all willing carry around in our pockets a device whose content is largely designed to modify our behavior and extract our time and money. Making “computer” mean computer-feelings and not computer-devices shifts the boundaries of what is captured by the word. It removes a great many things – smartphones, language models, “social” “media” – from the domain of the computational. It also welcomes a great many things – notebooks, papercraft, diary, kitchen – back into the domain of the computational. I love the feeling of a personal computer, one whose purpose primarily resides in the domain of the individual and secondarily supports the social. It’s part of what I love about the some of the ideas embedded in local-first, which start from the principle of owning and prioritizing what you do on your computer first and foremost, and then secondarily syncing that to other computers for the use of others. Email · Mastodon · Bluesky
