Google is rolling out an update for reCAPTCHA that utilizes QR codes that must be scanned with a mobile device rather than clicking on pictures or typing out warped text.
This will mean that GrapheneOS users must install Google Play Services to pass reCAPTCHA prompts, or use a secondary mobile device to pass reCAPTCHA prompts.
This is not limited to mobile devices. If you encounter the new reCAPTCHA prompt on a PC, you will be unable to pass without a mobile device that has Google Play Services, or the reCAPTCHA iOS app installed.
If you do not have Google Play Services installed and attempt to pass a reCAPTCHA that uses mobile device verification, you will be redirected to this support page for incompatible mobile devices.
I understand GrapheneOS supports Google Play Services, but I thought I should share these findings here as there are people who would prefer not to install Google Play Services that will be negatively affected by this.