The email, shared on Twitter by @smithsam and noted by TechCrunch, said: "Starting tomorrow May 24, 2018, access to the Instapaper service will be temporarily unavailable for residents in Europe as we continue to make changes in light of the General Data Protection Regulation (GDPR), which goes into effect May 25, 2018. We apologize for any inconvenience, and we intend to restore access as soon as possible."

While it's still unclear what specifically Instapaper feels is out of compliance, Brian Donohue, an engineering manager from parent company Pinterest, pointed his Twitter followers to Instapaper's privacy policy, which he said hasn't been changed in years. He is, he tweeted, "actively working on resolving it."

When reached for comment, a Pinterest spokesperson said, "Instapaper is temporarily unavailable for users in Europe as we make some changes for GDPR. We plan to bring the service back online as soon as possible, and will keep our users informed of any updates."