Proton Mail allows you to customize the layout of your inbox and email composer. There are several views to choose from. All views offer the same functionality while enabling you to customize your inbox’s appearance to your preferences.
To change the layout of your inbox and composer:
1. Log in to Proton Mail at mail.proton.me(new window) and click Settings → Go to settings → Proton Mail → Appearance.
2. Select the view you want for your inbox and composer.
Your inbox will now display messages according to your chosen format.