Describe the bug

When setting an attribute value to a string (eg: <input type=hidden name="foo" value={bar} />), if the string include a line break (eg: \n or \r\n), the HTML sent to the browser results in the the value being escaped. After hydration occurs, the value is reset to the expected value.

Reproduction

• Clone https://github.com/moatra/attr_enc_newline
• npm install
• npm run dev
• Open localhost:3000 and ensure javascript is enabled on the page.
  • Continuously submitting the form will not result in excessive escaping.
  • If you spam submit fast enough (ie, before hydration completes), you will see excessive escaping.
• Open localhost:3000 and ensure javascript is disabled on the page (to prevent hydration).
  • Continuously submitting the form will result in excessive escaping.

Logs

No log output

System Info

❯ npx envinfo --system --binaries --browsers --npmPackages "{svelte,@sveltejs/*,vite}" System: OS: Linux 5.15 Fedora Linux 35 (Workstation Edition) CPU: (16) x64 AMD Ryzen 7 3700X 8-Core Processor Memory: 20.63 GB / 31.33 GB Container: Yes Shell: 5.1.8 - /bin/bash Binaries: Node: 16.13.0 - /usr/bin/node npm: 8.1.0 - /usr/bin/npm Browsers: Firefox: 96.0 npmPackages: @sveltejs/adapter-auto: next => 1.0.0-next.30 @sveltejs/kit: next => 1.0.0-next.288 svelte: ^3.44.0 => 3.46.4

Severity

serious, but I can work around it

Additional Information

No response