Csp

Recharts is usually one of the easier charting libraries to live with under Content Security Policy. That’s the good news. The bad news: teams still break dashboards with CSP all the time, usually because they copy a broad policy from somewhere else, tighten it blindly, or blame Recharts for behavior caused by their own app shell, analytics, or CSS-in-JS stack. If you’re running Recharts in a React app, most CSP issues come from the environment around the charts, not the chart library itself. Recharts renders SVG. That’s a lot friendlier than libraries that depend on eval, dynamic code generation, or canvas hacks. Still, there are a few predictable ways to mess it up. ...

Remix Icon is easy to drop into a project, which is exactly why people ship it with a sloppy CSP. I’ve seen this a lot: someone adds the Remix Icon CDN snippet, the icons don’t render, they get a wall of CSP errors, and the “fix” becomes style-src 'unsafe-inline' plus a couple of random hostnames copied from the console. That works, but it’s the kind of fix that quietly makes the policy worse every time the app changes. ...

Bulma is one of the easier CSS frameworks to secure with Content Security Policy. That’s mostly because Bulma itself is just CSS. No bundled JavaScript, no weird runtime code generation, no framework magic that sneaks in inline scripts behind your back. That said, real Bulma sites rarely stay “just CSS” for long. You add a navbar burger toggle, a modal, analytics, a consent banner, maybe a form widget, and suddenly your clean CSP turns into a pile of exceptions. ...

Turret CSS is just CSS, so on paper CSP should be easy: allow your stylesheet, block the weird stuff, move on. In practice, teams still break production layouts with CSP all the time. I’ve seen the same pattern over and over: someone tightens style-src, the app ships, and suddenly Turret CSS “doesn’t work.” Usually Turret isn’t the problem. The policy is. More specifically, the policy was written with JavaScript in mind and nobody checked how styles are actually loaded, injected, or modified across the app. ...

If you’ve ever dropped a Vimeo embed onto a page and then wired up the Vimeo Player API, you’ve probably hit the classic wall: the iframe renders, but the API fails in weird ways, or the iframe is blocked entirely by CSP. This happens a lot because Vimeo embeds are one of those features that cross several CSP directives at once. You’re not just allowing a script. You’re allowing a framed document, cross-origin messaging, and sometimes extra assets depending on how you load the player. ...

If you use Aragon icons and your CSP is even slightly off, the breakage is usually annoying, subtle, and easy to misdiagnose. You see missing icons, blank squares, CSP console noise, or everything works locally but fails in production. I’ve hit this enough times to have strong opinions about it: most CSP problems around icon libraries come from guessing which directive applies. People tweak default-src, maybe throw in img-src data:, and hope for the best. That’s not how CSP works. ...

Teams usually discover CSP problems with Linaria the annoying way: everything works in development, then production gets a stricter policy and styles start disappearing. I’ve seen this happen when a team moves from a relaxed policy to something closer to a real production header, like the one headertest.com sends: content-security-policy: default-src 'self' https://www.googletagmanager.com https://*.cookiebot.com https://*.google-analytics.com; script-src 'self' 'nonce-MjgzMGM0NjctNzg4MS00NTNiLThkN2UtNjY3N2VmMTRlOGUy' 'strict-dynamic' https://www.googletagmanager.com https://*.cookiebot.com https://*.google-analytics.com; style-src 'self' 'unsafe-inline' https://www.googletagmanager.com https://*.cookiebot.com https://consent.cookiebot.com; img-src 'self' data: https:; font-src 'self'; connect-src 'self' https://api.headertest.com https://tallycdn.com https://or.headertest.com wss://or.headertest.com https://*.google-analytics.com https://*.googletagmanager.com https://*.cookiebot.com; frame-src 'self' https://consentcdn.cookiebot.com; frame-ancestors 'none'; base-uri 'self'; form-action 'self'; object-src 'none' That header is realistic because it shows the usual compromise: strong script controls, but style-src 'unsafe-inline' left behind because CSS tooling got messy. ...

PDF.js is one of those libraries that looks simple until CSP gets involved. You drop in the viewer, load a PDF, and everything works locally. Then you turn on a real Content Security Policy and suddenly the worker fails, fonts disappear, images stop rendering, or the whole viewer goes blank with a useless console error. I’ve hit this a few times. The pattern is usually the same: people start with a generic CSP, then keep adding exceptions until the app works again. That usually ends with unsafe-inline, unsafe-eval, and a policy that technically exists but doesn’t really protect anything. ...

I’ve seen the same pattern over and over: a team adopts a utility-first CSS framework, ships fast, then bolts on CSP later and wonders why the site breaks in weird places. Pharaoh CSS is no exception. The good news is that CSS-heavy sites are usually easier to lock down than JavaScript-heavy apps. The bad news is that most teams still start with a lazy policy like style-src 'unsafe-inline', leave it there forever, and call it “good enough”. It usually isn’t. ...

bare.css is the kind of CSS library that security folks usually like: tiny, boring, and not trying to be a JavaScript framework in disguise. That changes the CSP conversation quite a bit. If your site uses bare.css and almost nothing else, you can usually run a very tight policy. If your “simple” site also includes analytics, consent banners, embedded forms, tag managers, and a couple of convenience scripts, your CSP gets messy fast. I’ve seen plenty of “minimal” websites end up with a header that looks like an ad-tech startup wrote it. ...