How to Handle GZIP-Encoded Content in PhantomJS
Diagnose GZIP responses in PhantomJS with request hooks, rendered-page checks, controlled experiments, fixes, and a ScreenshotNeo alternative.
Engineering
Puppeteer, Playwright, Selenium and headless Chrome, and what they take to run well.
Why PhantomJS 2.0 Is Slow and How to Improve Performance
PhantomJS 2.0 slowness can come from page scripts, network waits, or rendering. Measure each stage, then reduce only the work your task does not need.
Is `page.evaluate()` in PhantomJS Vulnerable to JavaScript Injection?
`page.evaluate()` is not inherently an injection flaw. The risk appears when untrusted input becomes JavaScript source; here’s how to identify and fix that boundary.
Why Selenium Scroll Behavior Differs Between Firefox and PhantomJS
Firefox and PhantomJS do not share the same automation stack or scroll commands. Identify the scrolling surface and command first, then reproduce the result with matching conditions.
How to Read Text Inside a User-Agent Shadow Root
Learn why user-agent shadow roots return null, how to read open roots, and what JavaScript and Playwright can and cannot access.
Why PhantomJS Fails to Load the Entire Page in Time
PhantomJS’s load callback is not proof that every request or async render is finished. Learn how to diagnose timeouts and define page readiness correctly.
Why Selenium Grid Screenshots Have Different Sizes Across PCs
Grid screenshots come from remote nodes. Learn to control window geometry, measure PNG pixels, diagnose node differences, and capture reliably.
How to Make html2canvas Captures Consistent Across Runs
Make html2canvas output repeatable by fixing geometry, fonts, images, dynamic state, CORS, and export timing with a deterministic capture recipe.
Why html2canvas Cannot Capture Google Maps and Charts
html2canvas rebuilds DOM and CSS, so cross-origin map tiles and charts can disappear or taint the canvas. Learn the reliable fixes.
Why html2canvas Takes So Long to Capture Screenshots
html2canvas rebuilds an image from DOM and CSS data instead of saving browser pixels. Learn how to find the slow phase and reduce unnecessary work.
How to Render Absolutely Positioned SVGs Correctly with html2canvas
Debug cropped or shifted absolutely positioned SVGs in html2canvas with a reproducible workflow, bounds checks, rendering options, and fixes.
Why HTML2Canvas ForeignObjectRendering Captures Only the Viewport
ForeignObjectRendering follows the browser viewport by default. Learn how to set full-page dimensions, avoid canvas limits, and fix cut-off captures.
How to Visually Test D3, Highcharts, and SVG Charts
Build stable chart screenshot tests for D3, Highcharts, and SVG, then pair pixel diffs with accessibility and interaction checks.
How to Create an Image From the DOM Using Web Workers
Learn how to turn a DOM element into a downloadable image with html2canvas, OffscreenCanvas, and a Web Worker—without freezing the UI.
Why Chrome Calculates the Wrong Element Width and How to Fix It
Chrome usually reports a different box, not a wrong width. Learn how every width API works and fix scrollbars, transforms, rounding, and CSS constraints.
Why html2canvas Scrolls the Page to the Top and How to Fix It
Learn why html2canvas jumps to the top, how scroll offsets and nested containers affect captures, and the reliable fixes for browser and server screenshots.
How to Prevent html2canvas Resources Loading on Every Loop
Stop html2canvas from reloading images in every capture by preserving its shared cache, stabilizing cloned resources, and handling CORS correctly.
Why WebDriver Screenshots Fail When the Machine Is Locked
Locked desktops can remove the framebuffer WebDriver needs. Learn why screenshots turn blank or black and how to build reliable headless capture.