LastPass provides a cloud based hosted password manager solution. Here is a step by step guide to setting up LastPass to auto-login to your ProtonMail account.
To set up your Login password:
1) Go to the Sites tab
2) Click on Add Site
3) Configure you ProtonMail login and click on the Save button.
*Please note that our current login URL is: https://mail.protonmail.com/login. This may change in the future.
To configure your Mailbox password login:
1) Go to the website login page
2) LastPass will autofill the username and password as normal.
3) Then click the LastPass logo in the browser, then click on matching sites.
4) Then Click on Edit
5) Next, click on Edit Form Fields
6) Click on Add Form Fields
When you click on Add Form Fields the follow will appear, fill it in as below. Change Field Value to your mailbox decryption password
Then next time you login to Protonmail it will auto-fill the username and password.
Click on login, it will ask for the mailbox decryption password, LastPass will now auto-fill this is too.
If you experience any trouble with your LastPass manager working with your Mailbox password, please ensure you are using the latest version of Lastpass. This may require you to manually update the app. You can learn more here.
For more information on how to setup LastPass on your mobile device please see this article provided by Last Pass
This guide was brought to you by your ProtonMail community member.
Thank you @RedPacketSec!