Searching for a URL generates an error

[kesara]

Searching for a URL gives Invalid search expression error.

Example: https://mailarchive.ietf.org/arch/search/?q=https%3A%2F%2Fgithub.com%2Frfc-format

Works fine if double quotes are used: https://mailarchive.ietf.org/arch/search/?q=%22https%3A%2F%2Fgithub.com%2Frfc-format%22