Practical CSS and JavaScript snippets, use cases, UX hacks — with ready-to-paste code for JustZix.
No posts match your search.
Four small editor UX changes that together change how it feels day to day: a line-count badge in the CSS/JS/Actions tabs (v3.2.82), a 10→14 px scrollbar (v3.2.80), an 8→12 character action label limit (v3.2.81), and a reorganized folder toolbar (v3.2.80).
Rendering 700 log entries in the Output Console dropped from ~5 seconds to ~100 milliseconds (v3.2.30). The first extension window in a shadow DOM — a step toward isolating page styles from the extension UI, plus a serious performance win.
A dropdown in the AI Helper window header (v3.2.81) with two options: copy the whole conversation as Markdown, or copy the last API input with the full conversation context. The "move an idea from one domain to another" workflow stopped requiring manual copy-paste.
The context meter in the AI Helper (v3.2.71–73) no longer estimates — it now uses the actual token counts from the provider API (Anthropic, OpenAI, Gemini), broken down into fresh input / cache / output. Realistic AI cost without calculators.
The AI Helper window (v3.2.76) renders as a shadow root, so the page CSS cannot leak into the extension UI anymore. It works identically on play.google.com, Notion and every aggressively styled domain.
The browser-action popup and every modal in the extension finally have full dark mode. A new auto theme follows the operating system. The theme picker has been rebuilt as 3 buttons (light / dark / auto) instead of one cycling button.
A full rebuild of the Network tab in the Output Console: two domain fields with many entries via "|", Alt+click to add instantly, exponential sliders with input fields, resizable DataLayer columns, long-URL shortening.
The × in TEMP CSS/JS used to wipe the content — fixed in v3.2.2. Plus a new "clear" button with undo (v3.2.3). Two intents, two buttons.
The old "API help" under Ctrl+Shift+H became a complete two-column guide to the on-page extension UI — 8 sections, works globally on every page, in 8 languages. From v3.0.0 and v3.0.1.
Three new shortcuts from v3.2.4 open the JustZix edit panel in a separate browser window, auto-select the first active rule on the current page and land on the CSS, JS or Actions tab. The same shortcuts inside the panel switch tabs.
JustZix now ships two built-in tutorial engines: one in the edit panel, the other directly on the page. 19 steps of the "Your first project" scenario, copyable code snippets, 8 languages, Esc closes it.
Sites with the strictest CSP — Facebook, X, GitHub — block ordinary JS injection. JustZix gets through with a three-tier strategy: chrome.userScripts, new Function, blob-script. Zero configuration in 99% of cases, a one-time opt-in for the rest.
Ready-made rules for Slack, Trello, Discord, Outlook, Notion, GitHub, GitLab, Telegram and Gmail — density, sidebars and a focus mode.
Ready-made rules for Wikipedia, Medium, BBC, Goodreads, Hacker News and Stack Overflow — reading width, typography, dark and sepia modes.
Ready-made rules for Netflix, Disney+, Spotify, SoundCloud, Twitch, Vimeo and YouTube — stop autoplaying trailers and trim recommendation rows.
Ready-made rules for Amazon, eBay, AliExpress, Etsy and Allegro — hide sponsored listings, pressure counters and cross-sell carousels, surface the price.
Ready-made CSS and JS rules for YouTube, Reddit, X, Instagram, Facebook, TikTok, Threads, Pinterest and LinkedIn — hide the "For you" feed, suggestions and counters.
A new per-rule-set option stops JavaScript from re-running on SPA navigation — no more duplicated listeners and parallel intervals.
The Network tab in the Output Console has a full set of filters: by domain (Domains+/Domains-), by size and by time — plus click-to-add domains.
Every built-in JustZix keyboard shortcut in one place: code editors, the console, the Output window, the Network tab, TEMP windows and action shortcuts.
A practical guide to diagnosing and fixing differences between devices in JustZix using the sync history and the full resync.
The Status tab in the JustZix sync panel now shows a sync history, the state of your library on the account and a full-resync button.
JustZix detects SPA navigation via pushState — rules, action bars and windows matched to a URL path turn on without a manual page reload.
JustZix cloud sync now covers your theme, interface language and usage statistics summed across every paired device.
Four new AI Helper tools: the assistant tests code in TEMP windows, reads errors from the page console and creates not just rules but action bars and buttons.
Open the JustZix editing panel and the Dashboard greets you — tiles with your library inventory, usage stats, extension health and shortcuts back to recent work.
Reshape the Booksy dashboard with JustZix — a denser calendar, highlighted today and unconfirmed appointments, hidden promos and a distraction-free focus mode.
Reshape Allegro with JustZix — hide sponsored listings, get a denser results grid, highlight free delivery and Smart, and remove banners and carousels.
Hide Pro banners and template promos, enlarge the editor canvas and declutter Canva side panels with a few CSS and JS rules in JustZix.
Hide promoted posts, the "People you may know" modules and the right-hand news rail. A calmer LinkedIn feed with a few CSS and JS rules.
Densify product and order tables, highlight low stock and unpaid orders, hide upsell banners — ready-made CSS and JS rules for the Shopify admin.
Hide plugin upsell notices, declutter the admin menu, widen the post editor and pin the Publish box — ready-made CSS and JS rules for wp-admin.
Declutter and reshape Gmail, Google Calendar, Docs and Sheets: hide Meet and promo panels, compact the inbox, widen the reading pane, add a focus mode.
Reshape Notion to fit you: full-width pages, a focus mode, custom fonts, styled callout blocks, zebra-striped database rows and sticky table headers.
A practical guide to moving userscripts to JustZix rules: how the URL-matched rule model compares and when to use which tool.
Clean tracking parameters from links, neutralise tracking pixels and tidy shared URLs with defensive, copy-paste JustZix rules.
Widen code views, pin file headers and tame GitHub UI noise with practical JustZix CSS rules built for developers who read a lot of code.
Hide promoted posts, suggested content and engagement bait on Reddit and X with scoped JustZix CSS rules you can copy and paste.
Hide Shorts, kill the end-screen clutter and lock a default playback speed on YouTube with copy-paste JustZix CSS and JS rules.
A practical guide to enhancing images on any page: hover-to-zoom, forcing eager loading, and adding a one-click download button with JustZix.
Replace broken or hidden custom video players with the browser native control bar using one JustZix JavaScript and CSS rule.
A JustZix rule that pauses and mutes autoplaying video and audio the moment it starts, so pages open quietly without surprise sound.
Use the Picture-in-Picture API with a JustZix rule to pop any video into a floating window, even on sites that hide the native button.
Add custom playback speed controls to every video element with a JustZix JavaScript rule, including keyboard shortcuts and a floating speed badge.
Turn handy one-off scripts into JustZix action buttons: copy a page as markdown, strip tracking parameters, and open external links in new tabs.
Bind keys to scrolling, navigation and clicks on sites that lack shortcuts. A JustZix JavaScript rule turns any page into a keyboard-driven app.
Stop clicking "show more" and "next page". A JustZix JavaScript rule can expand collapsed sections and load every page for you.
Cookie consent popups interrupt every visit. Use a small JustZix JavaScript rule to dismiss them automatically the moment they appear.
Some sites block text selection, copying and the context menu. Re-enable all of it with three short JavaScript snippets and one CSS rule.
A small JustZix JavaScript snippet that measures any article and shows a floating reading-time and word-count badge.
Strip recommendation rails, sticky bars, and toxic comment threads from any article with a few targeted JustZix display rules.
Swap glaring white pages for warm, low-glare reading surfaces with CSS recipes for sepia, cream, and gentle paper tones.
Why line length makes or breaks readability, and the exact CSS rules to lock any article to a comfortable measure.
Turn any cluttered article page into a clean, calm reading view using a handful of CSS rules injected by JustZix.
Style scrollbars and build high-contrast or grayscale themes for any website with JustZix CSS rules. Practical accessibility-focused recipes.
Make cramped websites readable by tuning font size, line height and content width with JustZix CSS rules. Copy-paste recipes for a calmer page.
Replace ugly or hard-to-read typefaces on any site using JustZix CSS rules. Recipes for system fonts, custom web fonts and code-friendly monospace.
Recolor links, buttons and highlights on any site with JustZix CSS rules. Practical recipes for overriding accent colors without touching the markup.
Turn any bright website into a comfortable dark theme with a few JustZix CSS rules. Copy-paste recipes for filter-based and native dark modes.
Strip sponsored posts, suggested content, and noisy sidebars from your social feeds with a full set of copy-paste JustZix CSS and JS recipes.
Sticky navbars eat your screen and hide text when you jump to anchors. Reclaim the space with these copy-paste JustZix CSS recipes.
Hide banner ads, ad slots, and sponsored content blocks using lightweight JustZix CSS rules that load instantly with no extra ad-blocker.
Stop modal newsletter popups and exit-intent overlays from interrupting your reading with ready-to-copy JustZix CSS and JavaScript rules.
Kill cookie banners and consent overlays with a few copy-paste CSS and JS rules so pages load clean every single time you visit them.
A roundup of the latest JustZix update: the new AI Helper assistant, in-editor code search and the rebuilt 6-tab Output Console.
The new in-editor search bar: match counter, blue and yellow highlighting, navigation arrows and every keyboard shortcut for CSS and JS editors.
An honest look at using OpenAI, Anthropic and Gemini inside JustZix AI Helper: how all three work the same, the real differences, and switching.
AI Helper never silently changes your setup. It tests code in visible TEMP windows and every folder, group or rule needs your explicit OK.
A hands-on walkthrough: describe a goal to AI Helper, watch it inspect the page, test in a TEMP window, and save the rule after your OK.
How AI Helper inspects the live DOM with query_page and reads your rule library with list_structure, and why on-demand beats dumping the page.
Where AI Helper stores your API keys, why calls go through the background worker, the per-key optional cloud sync, and honest key hygiene.
How AI Helper runs an agentic loop: the @@JZ_TOOL@@ protocol, the 8-step limit, every tool, and why it works the same on all providers.
Step-by-step: get an OpenAI, Anthropic or Gemini API key, enter it in JustZix Settings, pick a default provider and choose a model.
AI Helper is a chat assistant living inside any page. Bring your own API key, give it page context, and let it build CSS/JS rules with you.
Greasemonkey is Firefox-only. Here is an honest guide to the Chrome equivalents: Tampermonkey, Violentmonkey and JustZix, with how to pick the right one.
Learn how to run JavaScript on any web page: the DevTools console, bookmarklets and a persistent rule-based approach with JustZix, plus real examples.
Learn how to add custom CSS to any website. DevTools, browser tools and an extension approach explained, with a step-by-step JustZix walkthrough and examples.
Want a safe Stylish alternative for custom CSS? An honest look at the Stylish history, the open-source Stylus, and JustZix — with no telemetry.
Looking for Tampermonkey alternatives? An honest comparison of Violentmonkey, Greasemonkey, Stylus and JustZix — what each does well and when to pick it.
JustZix's Output Console has a Network tab that captures requests via chrome.webRequest — in-tab, with a background buffer, filters and sliders.
JustZix's Output Console is a read-only log viewer inside the tab — 6 tabs for console, network, errors and dataLayer, with live filters and search.
Make JustZix rules behave differently by time of day or weekday: a work-hours focus mode, a night warm-tint, weekend-only layouts and more.
Debug responsive layouts without DevTools: a live viewport badge, breakpoint name, overflow finder and grid ruler injected straight onto the page.
Build a JustZix action button that copies a page or your text selection as clean Markdown — headings, links, lists, code — with no nav or ads.
Inject a JavaScript accessibility overlay: spot missing alt text, unlabeled inputs, low contrast and heading jumps in seconds, on any page.
Inject a @media print stylesheet to fix printing and Save as PDF on sites that print badly. Hide nav, control page breaks, save ink.
Watch a price or availability element with MutationObserver, alert when the price drops below a threshold or a sold-out item returns to stock.
Neutralize dark patterns with CSS and JavaScript: hide fake countdowns and fake viewer counts, freeze timers and un-check pre-ticked add-on boxes.
Soft paywalls hide an article already in the DOM behind an overlay and a scroll lock. Learn to remove the overlay, unlock scroll and un-blur the text.
Intercept fetch and XMLHttpRequest in the browser to return fake JSON, simulate latency, 500 errors and empty lists — no mock server required.
Pin yourself into any A/B test bucket or feature-flag variant by overriding the cookie or localStorage value the site uses, so QA can test every branch.
A tester builds the QA toolbar themselves and hands it to the team with one TTL link. How to set it up, and when to use a link versus sync.
Most of a userscript pastes over unchanged. What works differently — the metadata header, the GM_* functions — and what replaces it.
Injected JavaScript runs with the full rights of the page you visit. What a snippet can really do, what it cannot, and whom to trust.
Enter a sync key on another computer and your rules are just there. How it works under the hood — and why JustZix will not overwrite your work.
Five rules you keep in your head. Fifty you do not. How the four-level JustZix hierarchy scales to 100+ rules.
The URL pattern decides where a rule runs. Five patterns worth knowing, how they stack in the hierarchy, and the common mistakes.
window.JUSTZIX logs straight into the Output Console window — diagnose a page without opening DevTools. Usage patterns and pitfalls.
JustZix actions can call each other. With window.JZ you build multi-step workflows from buttons — with no library.
A rule built on a .css-1a2b3c class dies at the next site deploy. Four rules for writing rules that survive a redesign.
A rule runs once, but pages change after they load. A MutationObserver makes the rule react to new elements in the DOM.
Three universal JustZix actions useful almost everywhere: copying a clean URL, exporting a table to CSV and Picture-in-Picture.
How long will this article take? A JustZix rule adds a bar at the top of every text with the word count and an estimated time.
Parallax, carousels and auto-playing video can be tiring. A CSS plus JS rule quiets the motion on any page.
The "wait 5 seconds" pages live off your time. A JustZix rule extracts the destination URL and jumps past the redirect at once.
One CSS rule shows which links you have already opened. Plus: why the :visited selector is so heavily restricted by browsers.
Sticky headers and floating bars can eat a third of the screen. How to unstick or hide them with one CSS rule.
Comment sections and long posts hide content behind show more. A JustZix rule with a MutationObserver expands them all automatically.
The built-in reader mode is hit-or-miss. Build your own as a JustZix action — it strips the page to the article, exactly how you want.
Hover a thumbnail, see an enlarged preview by the cursor. A lightweight pure-JavaScript lightbox as a JustZix rule — no library.
Content split across 40 pages? Auto-pager fetches the next page and appends it when you reach the bottom. Infinite scroll in one rule.
The built-in player stops at 2x. A JustZix rule adds keyboard playbackRate control to every HTML5 video.
A page blocks text selection and right-click? One JustZix rule lifts the block — CSS plus capture-phase event interception.
Pages with a strict Content-Security-Policy block foreign scripts. JustZix still injects your JS there — via chrome.scripting.executeScript and a postMessage bridge.
JustZix Output Console now captures uncaught exceptions and unhandled promise rejections, not just explicit console.log. What changes, and what it still will not catch.
Every JustZix dev window opens as a persistent pane or an ephemeral TEMP one. A simple decision model: when to pick which, and how to promote one into the other.
Summon a CSS, JS, REPL or Output window on any page with a Ctrl+Alt shortcut. TEMP panes vanish on reload — zero config, zero trace in your rules.
PerformanceObserver captures LCP (Largest Contentful Paint), CLS (Cumulative Layout Shift), INP (Interaction to Next Paint). Inject once via a JustZix JS rule, Output Console shows results for every page you visit. No Lighthouse, no F12.
Sponsored posts mix into social media feeds alongside organic content. CSS selectors miss them (random class hashes). JustZix recipe: CSS attribute matchers + JS MutationObserver with text matching for 3 platforms.
Tampermonkey/Greasemonkey are userscripts (JS only, header metadata). JustZix is userscripts + userstyles + UI layer (action bars, panes, snap dashboard). Feature-by-feature comparison + migration of 3 typical Tampermonkey scripts to JustZix rules.
YouTube default UI: Shorts spam, Suggested videos interrupt flow, no shortcut for "skip intro/sponsor". 6-rule JustZix pack: CSS hides + JS auto-skip + keyboard shortcuts (J/L jump, S sponsor skip, Shift+S share screenshot).
Stylish (controversial) and Stylus are classic CSS-injection extensions. JustZix does the same + JS rules + action bars + 4 window types + snap connections + sync + share TTL links. Step-by-step migration with feature-by-feature comparison.
The floating button is "the entrance to JustZix" on every page — a 3-letter drop per folder, 4 states (on/mixed/off/globally-off), drag+snap with bars/panes, right-click context menu, popup widget toggling all rules. Full anatomy from position to keyboards.
All 3 most popular AI chat apps have default UIs tuned for newcomers. For power users: too-narrow message bubbles, weak code blocks, "Upgrade to Pro" overlays. CSS snippets + JS observer in JustZix, one click, always there.
INPUT is a native <input type="text"> in the action bar. Enter → blur → run code. Persistent per-tab memory (sessionStorage + chrome.storage.local). Key difference vs TEXTAREA: Enter triggers the action. Use case: command bar, quick search, filter override, custom URL navigation.
SELECT is a dropdown in the JustZix action bar. Two variants: static (hardcoded options in the schema) and js (code dynamically generates options). The first is great for fixed presets (Light/Dark, language pick), the second for dynamic lists (DOM categories, hotkeyed bookmarks).
BUTTON is the oldest and most-used JustZix action type. Click = run code in MAIN world. No state, no memory — a pure function. Full customization (background, text colour, padding) + customStyles for pixel-perfect integration with the action bar.
Since v2.13.42/55/70 right-clicks on pane headers (CSS / JS / JS Console / Output Console) open a contextual menu: disconnect snap connections, disable pane, change font + size — without going back to the options page.
Four capture-phase document listeners (v2.13.75 + v2.13.78): Ctrl+Shift+L (clear), Ctrl+Shift+S (toggle search), Ctrl+Shift+K (cycle viewMode), Ctrl+Shift+H (API help popup). All active when at least one Output Console is rendered on the page. Plus a draggable help popup (v2.13.80).
The TEXTAREA action (v2.13.21) is a native <textarea> in the JustZix action bar. Per-tab persistent memory (sessionStorage + chrome.storage.local backup). Enter = native newline (NOT blur). Code fires on blur. Use cases: QA scratch pad, comment drafts, SQL/curl/JSON snippets per domain.
A guide to all JustZix windows on the frontend and action types. Four pane types (CSS pane / JS Console / JS pane / Output Console), the two strongest actions (TOGGLE3 / SLIDER), the window.JZ + window.JUSTZIX API, and snap connections to lay it all out as a mini-dashboard. Full map of "mini-IDE in a tab" — what to pick when, and how it all fits together.
CSS pane + JS pane + JS Console + Output Console + action bars + floating button — all live in a shared snap ID space. Drag one near another → they snap into a group. Drag the group → moves everything together. Anchor positioning keeps the layout stable across window resizes.
Output Console (v2.13.66+) is the 4th window type in JustZix. A read-only log viewer captures all page console.log/warn/error/info/debug (sync + async). A dedicated window.JUSTZIX.log channel (primary since v2.13.76, brand-named, vanishingly small collision risk) with viewMode [C/J/C+J]. Per-level filters + search + 2000 lines. CSP-immune via chrome.scripting injection (v2.13.74).
The SLIDER action is a native <input type="range"> in the action bar. Live drag updates memory without firing code (input event), release fires code (change event). Value is a Number, not a String. Use cases: brightness, zoom, font-size, animation speed — driven like a physical fader.
The TOGGLE3 action is a segmented control with exactly 3 states. Each state has its own label, value, colour and JS code. Memory persists the active state per action. 5 configurable colours: active bg/text + inactive bg/hover/text.
Every JustZix action gets two MAIN-world namespaces: window.JZ (action helpers — click/value/setValue on data-jz-action-* elements) and window.JUSTZIX (logger — log/warn/error/info/debug into Output Console). Brand-named JUSTZIX never collides with page scripts (Google Ads owns window.JZ on its pages). Build mini-apps where buttons click other buttons, sliders drive CSS variables, and Output Console replaces DevTools.
Persistent JS code with Ctrl+Enter / click ▶ to run. No auto-execution on load. Dirty state, error overlay, per-tab sessionStorage. Use cases: destructive scripts + bulk operations.
A floating REPL window with command history, Ctrl+L = clear, Ctrl+Enter = eval. Captures console.log/warn/error/info from page context. Per-tab persistence.
A floating textarea injected on the page with live <style> injection (200ms debounce). Per-tab persistence, multi-pane, scope hierarchy. What it does and how to start in 30 seconds.
Five visual marking techniques for non-production environments: red banner, floating badge, favicon swap, viewport tinting, title prefix. Copy-paste CSS+JS for JustZix.
How to build your own QA toolbar: auto-fill forms, reset state, copy URL with auth token, fast-forward dates, debug requests. Everything in JustZix, no dev support needed.
Four JavaScript patterns to add your own keyboard shortcuts on any website. Without waiting for the author, without Vimium-style heavy extensions. Copy-paste for JustZix.
Four JavaScript snippets to verify GTM events fire at the right moment with the right payload. No production code changes. Copy-paste ready for JustZix.
Four ways to force dark mode on any site: invert filter, prefers-color-scheme override, CSS variables override, dedicated per-site theme. Copy-paste code for JustZix.
Five tested CSS and JavaScript snippets to hide cookie banners on any website. Copy-paste code that works immediately inside JustZix.