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Introducing new improved Proton Mail Bridge v3

Introducing the new and improved Proton Mail Bridge

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When it comes to emails, we know everyone has their own preferences. Some prefer to use our web or mobile apps, while others prefer to use their favorite email client, such as Outlook, Thunderbird, or Apple Mail. 

That’s why we created Proton Mail Bridge, so you can keep your existing email workflow while still benefiting from Proton’s end-to-end encryption. Last year, we gave Bridge a new design, making it easier to use. Today, we’re excited to announce major performance and stability improvements that will roll out to everyone in the coming weeks:

  • Syncing your inbox is up to 10 times faster.
  • Sending emails with large attachments is up to three times faster
  • You can now compose and send emails right away without waiting for your inbox to sync.

Bridge is available to everyone with a paid Proton Mail plan on Windows, macOS, and Linux. And for macOS users, Bridge now offers native support for Apple Silicon chips, offering a smooth and efficient email experience without compromising your device’s battery life.

Proton Mail Bridge user interface showing Status View

Under the hood – our new IMAP library

You’ll notice a vast performance improvement in this latest version of Bridge, making it easy for you to manage your emails from multiple devices and apps. Now, Bridge quickly syncs your emails when you first set it up or log in after a prolonged break, allowing you to get through your inbox much faster. 

Normally, when you mark an email as read, archive it, or delete it, your email app relies on the position of each message in your inbox to perform the relevant action. This becomes tricky when you use multiple devices or email apps — they all need to be in sync, otherwise the action could be performed on the wrong message. This means Bridge needs to notify all email apps of the changes you make to your messages.

To speed up this syncing process, we created a new IMAP library, Gluon, that uses a “snapshot” system, which assigns each email app its own snapshot of your inbox. This way, Bridge knows exactly which message your email app is referring to at any time, regardless of actions performed in other email apps, allowing bulk email actions to be handled entirely in memory. 

As with all our code, Gluon is fully open-source(new window), so you can inspect it or use it in your own projects.

Read the full story about Gluon, the high-performance IMAP library(new window)

Proton Mail Bridge user interface showing options to set up email client

Try the new Proton Mail Bridge

Starting today, we’ll begin rolling out the new Proton Mail Bridge to everyone. If you don’t currently use Bridge, now is the time to give it a try!

Thank you for choosing Proton Mail, and don’t forget to share your feedback via the dedicated reporting feature in the app.

Secure your emails, protect your privacy
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Andrzej Szafranski(new window)

Andrzej is a product manager focusing on improving and developing our Proton Mail and Core products. Before he joined Proton in 2019, he was building products and services in the big data space. He is passionate about online privacy and new technologies.

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