GitHub code search started requiring logins

Until recently, I was able to search code on GitHub without logging in as long as it was constrained to a single repository. Starting this week, I noticed that all searches now require logging in, both at home and at work. Has anyone else noticed this apparent change? Also, if this restriction applies to everyone, has there been any announcements?

Here's an example link:

https://github.com/openssl/openssl/search?q=OCSP_REQ_CTX_add1_header&type=code