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I have recently moved my website to a new domain. My old posts may reappear in your feed reader — sorry for the inconvenience! I redirect the RSS feed to the new domain, but you might want to update the URL in your reader. I've also merged my dev, photography, and personal posts into a single feed. If you're only interested in one of these categories, you can subscribe to the corresponding feed: All posts Software development posts Photography posts Personal posts I'll soon publish an update on my website redesign — stay tuned!
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 }); Reply via email
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: Copy Tab — copy browser links and titles in one click (as Markdown and rich text). 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). Reply via email
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: BrowserReloadBack Firefox 130YesYes Chrome 129NoYes Safari 18NoYes How does it work? I was surprised to learn that this autofill behavior is controlled via the autocomplete, that's 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"),outputElementNative=document.querySelector("#example-search-output"),performSearch_exampleSearch=e=>{e.innerText="";const t=document.createTextNode("Open the result for ");e.appendChild(t);const n=document.createElement("a");n.href="https://example.com",n.innerText=inputElementNative.value||"no text",e.appendChild(n)};document.querySelector("#example-search-form").addEventListener("submit",e=>{e.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. The second parameter to "replaceState" isn't used, but it's mandatory. If the argument is left out, the browser will throw an error: 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'll keep the solution here in case someone needs it, but usually it's 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"),outputElementCustom=document.querySelector("#example-preserve-output"),performSearch_examplePreserve=e=>{e.innerText="";const t=document.createTextNode("Open the result for ");e.appendChild(t);const r=document.createElement("a");r.href="https://example.com",r.innerText=inputElementCustom.value||"no text",e.appendChild(r)};document.querySelector("#example-preserve-form").addEventListener("submit",e=>{e.preventDefault(),performSearch_examplePreserve(outputElementCustom),history.replaceState({query:inputElementCustom.value},"")});const historyQuery=history.state?.query;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. Reply via email
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To protect against link rot and disappearing content, I save local copies of web pages I like into my web archive. Ideally, this archive is completely self-contained. I want a local copy of each page’s HTML and all the assets it depends on (CSS, images, scripts, and so on). I don’t want my archived pages fetching resources from the original website, which could disappear at any time. Initially, I was verifying self-containedness by hand. I’d open each saved page in a web browser, and check the browser dev tools. I’d check the Console tab for errors and failed requests, and watch the Network tab for requests going out to the internet. That approach was tedious and error-prone, and I wanted something better. I now automate the process using Playwright, a testing framework that allows you to control web browsers. I open each page using Playwright, and check if it’s making external requests. Detecting external requests in Playwright When you open a page in Playwright, you can subscribe to request events which tell you when the page issues a request. In this Python snippet, we start Playwright, start a WebKit browser, and open a new page. We tell the page to append external requests to a list, and then load example.com. We see that example.com makes two requests on page load: one for https://example.com, and one for a JavaScript file. from contextlib import closing from playwright.sync_api import sync_playwright with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, closing(browser.new_page()) as page, ): requests = [] page.on("request", lambda msg: requests.append(msg)) page.goto("https://example.com") print("requests:", requests) # requests: [<Request url='https://example.com/' method='GET'>, # <Request url='https://example.com/s.js' method='GET'>] In a more complex scenario, we might use Playwright to interact with the page after loading – for example, clicking a button or filling in a form, and then we could see the requests triggered by each action. Once we have a list of requests made by the page, we can inspect the url property to check if any of them were fetching from an external website. I wrote a function is_external_request to carry out this check: from playwright.sync_api import Request import urllib.parse def is_external_request(req: Request, original_url: str) -> bool: """ Check if a request has a different origin than the original URL. A request is considered internal if: - it matches the original URL exactly - it has the same scheme, host, and port as the original URL - it uses a `blob:` scheme (for example, in-memory media representations) """ if req.url == original_url: return False # Compare the scheme/host of the request to that of the original URL. org_url = urllib.parse.urlsplit(original_url) req_url = urllib.parse.urlsplit(req.url) if org_url.scheme == req_url.scheme and org_url.netloc == req_url.netloc: return False # Ignore blob: URLs, which are in-memory representation of some data, # and not an external request. # # Playwright detects blob: URLs when loading media files; for example # using the <audio> or <video> tag. if req_url.scheme == "blob": return False # Fail open: if we can't decide if a request was internal or external, # assume it was external. return True assert_page_is_self_contained(ctx, url) I’ve wrapped these two steps in a function assert_page_is_self_contained(ctx, url), which is part of my chives utility library. The function takes a Playwright Browser (or BrowserContext) and a URL, then: Opens a new page in the browser Loads the URL in the page Checks what happened when the page completes loading It throws an exception if there are any: Uncaught page exceptions or errors Console warnings or errors Non-GET requests Requests targeting external resources The function tries to trigger important network requests that might be skipped on the initial page load. For example, it evaluates the body’s offsetHeight to force a synchronous reflow, which causes the browser to request any lazily loaded images or fonts that might otherwise be missed. Here’s an example which verifies a file example.html from the working directory: from chives.browser_fixtures import assert_page_is_self_contained, file_uri from contextlib import closing from playwright.sync_api import sync_playwright with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, ): assert_page_is_self_contained(browser, url=file_uri("example.html")) I originally passed a Page as the first argument, but changing the function to take a Browser or BrowserContext lets it manage its own pages. It gets a fresh page for every verification, and closes it when it’s done. (The first time I ran this, I created a new page for every verification, and never closed them – my computer ground to a crawl as my script opened hundreds of browser tabs.) If you create a new context, you can emulate different browser settings, like location, locale, and window size. Here’s an example where we use contexts to test the same page in light/dark mode: with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, ): with closing(browser.new_context(color_scheme="light")) as light_ctx: assert_page_is_self_contained(light_ctx, url=file_uri("example.html")) with closing(browser.new_context(color_scheme="dark")) as dark_ctx: assert_page_is_self_contained(dark_ctx, url=file_uri("example.html")) In my web archive, I check every page in light/dark mode, and at 1×/2× pixel densities. It takes at least a second to run each verification, so I cache the results. As I save new pages, they’re added to a verification queue, and I’m warned of any missing assets. Unsurprisingly, the first run flagged many missing fonts and images, which I added to my local archive. Every saved page now passes cleanly. Browser is best-effort, but may still miss things Even with automated testing, it’s difficult to guarantee a completely self-contained archive. Different instances of a browser might load different assets, and a single page load might miss different variations: Responsive images – web pages can offer different sizes of an image, and the browser chooses a specific size based on the current window dimensions Appearance settings – a browser might load different fonts or images depending on light/dark mode Interaction-dependent assets – a web page might have assets that are only required on hover or user action You can mitigate some of this by testing with multiple contexts or adding post-load interactions, but every step makes the process take longer. Fortunately, most of the pages I save are simple, blog-style pages where I’ve stripped out the JavaScript. For my specific use case, initial load verification is more than good enough. Other uses for this code There are other projects where it could be useful to intercept and audit the requests made by a web page: Verifying your Content Security Policy (CSP). The CSP header restricts what resources can be loaded by a web page, and you could check that your configuration has the correct effect. Auditing login screens. You could check that sensitive pages don’t load any external scripts, which mitigates the risk of credential theft via a compromised third-party. Testing analytics and tracking. You could script user flows, like a shopping cart checkout, and confirm that tracking events fire correctly. I don’t do much front-end web development, but Playwright has become a key tool in my toolbox. I read a lot about people using AI agents and MCPs to interact with websites, but I prefer Playwright. It’s more fiddly and requires explicit instructions, but it’s constrained, deterministic, and I never have to worry about it doing something unexpected. [If the formatting of this post looks odd in your feed reader, visit the original article]
It’s four years since I bought a printer. I thought I would provide an update on running costs, print sales, and profit. I’m happy to be completely transparent about all this as I know it can be difficult to figure this out if you are thinking of creating your own printing business. January 11th 2026, 11:30am All the photos here are work shot in the last twelve months. Year Four Investment? Nothing other than consumables this year. I did purchase a high-spec film scanner last year, detailed here, but don’t consider that as part of this. The scanner has paid for itself several times over, and it may become a factor in future years (see below). Income Income is made up of sales through a local gallery that I am part of, along with web sales: 5,940.- CHF - sales through the gallery 80.- CHF - sales through web shop = 6,020.- CHF total income Total income is down about 50% compared to 2025. Costs I had to purchase consumables (paper and ink), at a total of 957.- CHF. That cost is included in the total here under the “print consumables” category. January 11th 2026, 3:30pm Rental cost of space in the gallery was reduced due to having overpayments of rent and my loan to the gallery, from the previous year(s), paid back to me. -1,500.- CHF - rental cost of space in the gallery -957.- CHF - print consumables (paper, ink) -1,138.- CHF - framing/mounting/postage -1,135.- CHF - commission to the gallery -300.- CHF - web shop subscription 0.- CHF - stripe / paypal fees 0.- CHF - advertising (none this year) = -5,030.- CHF total costs Total costs are down by about 60% compared to 2025. Total Profit 6,020.- CHF total income -5,030.- CHF total costs = 990.- CHF total profit A Quiet Year? Actually an average year. The previous couple of years were outliers, due to large orders, so really I’m back to normal in terms of sales. The key factors in managing to generate a [small] profit this year were: 1) no longer having to pay back the loan used to finance the printer, and 2) reduced rental cost of space in the gallery due to a previous loan to it being repaid. Also having to spend almost 1,000.- CHF on ink this year ate into profit. This is probably a “once every three years” cost given the rate I print at. The principal cost is rental of space in the gallery - in a normal year this would be 3,000.- CHF. Essentially this means, given the material cost of printing and framing/mounting and commission to the gallery, I need to make about 5,500.- CHF of sales to break even. Solar Eclipse, August 12th 2026 That’s a grind. However I did receive two substantial orders at the end of October, which haven’t made it in to this year’s figures and should boost next year’s. Maybe even a good sign for the year to come? At least now the original investment loan is repaid, the printing costs cover themselves in most years. I may look at offering scanning services now that I have a high-spec film scanner, which could become a scan + print service. More thoughts about that next time.
