PersistCSS

A CSS editor with Nord theme for modifying webpage styles

PersistCSS puts a real CSS editor in Chrome's side panel and keeps what you write. Test ideas, debug styles, and save what works. Write custom CSS directly on live websites, and PersistCSS remembers your styles by site and reapplies them automatically as pages load. It is built for designers, developers, QA testers, and anyone who needs to quickly experiment with layout fixes, visual tweaks, or site-specific style changes. Your CSS is saved locally by website, so you can keep iterating without starting over after every refresh. Features Side Panel CSS Editor Open PersistCSS from the Chrome toolbar and work in a full side panel editor while keeping the website visible. Per-Site Saved Styles Write CSS for the current website and keep those styles saved locally. They reapply early during page load on future visits, so your styling shows up with minimal flicker. Live Sync Across Tabs Changes apply to every open tab of a site in real time, not just the one you are looking at. Site Manager View, search, edit, enable, disable, or delete the CSS you have saved for any site. Live Preview See valid CSS changes update on the page as you type, without needing to click Apply. Apply When Ready Prefer manual control? Turn Live Preview off and apply changes only when you are ready. Pending Change Reminder PersistCSS lets you know when you have CSS edits that have not been applied yet. Automatic Drafts Unsaved edits are kept as a draft for each site, so switching tabs, closing the panel, or restarting Chrome will not lose work in progress. Syntax Highlighting & Linting Powered by Ace Editor with CSS syntax highlighting and lightweight lint feedback to catch common issues before applying. Element Picker Click an element on the page and PersistCSS works out the shortest selector that uniquely matches it, then inserts it into the editor. Aggressive Overrides Use the !important toggle when you need your custom styles to win against stubborn site CSS. Copy, Download, and Delete Copy your CSS, export it as a .css file, or delete saved styles with a confirmation step. Accessible by Design A high-contrast Nord theme that meets WCAG AA contrast guidelines, with visible keyboard focus indicators throughout. The editor can be left with the keyboard: press Escape to move focus out, then Tab carries on through Copy, Download, Delete and Apply CSS. Screen readers announce the editor by site name and read the action buttons in the order they appear on screen. Local-Only Storage Your CSS stays in Chrome's local storage on your device. PersistCSS has no backend and no analytics, so nothing is sent to the developer or to third parties. It asks for as few permissions as it can: the tabs and activeTab permissions have been removed. It reads the current tab's address to work out which site you are on, and does not store it. The only site names saved are the ones you write CSS for. New in 1.3.5 - Something not working? The About panel now has a Report a problem button. It opens a short form with your extension version already filled in, so you do not have to go looking for it first. There is no account to make, and an email address is optional: leave it blank and the report arrives with nothing attached that identifies you. PersistCSS is simple, private, and built for real-time CSS experimentation on the websites you work with most. Every feature is free and ungated. No account, no Pro tier, nothing locked behind a payment. It is a one-person labor of love that I use every day in my own work, and donations are welcome but never expected.