Translation: "The company @ProtonMail delivered IPs of climate activists to the police, after which the activists were arrested and searched. ProtonMail claims on its website, however, that it does not store the IP addresses of its users."
Source (in French): https://secoursrouge.org/france-suisse-securite-it-protonmai...
Translation (via Google Translate):
The year 2020 and 2021 was marked by the establishment and repression of a series of occupations in the district of Place Sainte Marthe, in Paris, in order to fight against its gentrification. Some 20 people were arrested, three searches were carried out and several people were sentenced to suspended prison sentences or to fines of several thousand euros (more info here and here). In addition, seven people are on trial in early 2022 for “theft and degradation in assembly and home invasion” following the occupation of a with a file of more than 1000 pages. During the investigation, the police focused on the collective “Youth For Climate”. In particular, they were able to use photos published on Instagram, even if they were blurred because of the clothes.
The police also noticed that the collective communicated via a protonmail email address. They therefore sent a requisition (via EUROPOL) to the Swiss company managing the messaging system in order to find out the identity of the creator of the address. Protonmail responded to this request by providing the IP address and the fingerprint of the browser used by the collective. It is therefore imperative to go through the tor network (or at least a VPN) when using a Protonmail mailbox (or another secure mailbox) if you want to guarantee sufficient security.