Urgent Mastodon Security Patch

⚠️ We are planning to release important security fixes for #Mastodon on July 6th, between 13:00 and 15:00 UTC. They will be available for the 4.1, 4.0 and 3.5 versions as well as a nightly release, to make the upgrade as small and painless for everyone as possible. Be ready to upgrade!