You can use newline characters in URLs
Summary
Daniel Lemire explains how newline and tab characters are treated in URLs under WHATWG standards, noting that such whitespace is considered an invalid-URL-unit validation error but is typically removed rather than terminating parsing. The post illustrates practical behavior with HTML examples and highlights data URLs as a special case that can embed content like images or SVGs, including how whitespace is handled in base64-encoded data. It also references a 2024 paper on parsing millions of URLs per second and provides context about the author and related resources.