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Sebastian Markbåge
4c2fc01900
We currently throw an error when disableJavaScriptURLs is on and trigger an error boundary. I kind of thought that's what would happen with CSP or Trusted Types anyway. However, that's not what happens. Instead, in those environments what happens is that the error is triggered when you try to actually visit those links. So if you `preventDefault()` or something it'll never show up and since the error just logs to the console or to a violation logger, it's effectively a noop to users. We can simulate the same without CSP by simply generating a different `javascript:` url that throws instead of executing the potential attack vector. This still allows these to be used - at least as long as you preventDefault before using them in practice. This might be legit for forms. We still don't recommend using them for links-as-buttons since it'll be possible to "Open in a New Tab" and other weird artifacts. For links we still recommend the technique of assigning a button role etc. It also is a little nicer when an attack actually happens because at least it doesn't allow an attacker to trigger error boundaries and effectively deny access to a page.