page.goto: net::ERR_CERT_AUTHORITY_INVALID

Why this happens

• The test environment uses a self-signed certificate or one issued by an internal company CA
• A local HTTPS dev server (mkcert, Vite's basic-ssl plugin, etc.) uses a CA installed on your machine but not in the CI runner or the Playwright browser
• A corporate proxy intercepts TLS traffic and re-signs it with its own certificate

How to fix it

1. For test environments you control, set `ignoreHTTPSErrors: true` in the `use` block of playwright.config.ts
2. Scope it to the non-production projects only, so a genuinely broken certificate on production still fails loudly
3. Better long term: give staging a real certificate (e.g. Let's Encrypt) so tests don't need the bypass at all

Example

              // playwright.config.ts
export default defineConfig({
  projects: [
    {
      name: 'staging',
      use: { baseURL: 'https://staging.internal', ignoreHTTPSErrors: true },
    },
  ],
});