White Screen Bug

After click “Compose New Message” a new message window opens but the background is cover with white and freezing.

@alpaqut To be able to act on this, we need the setup info requested by the template:

## Setup
<!-- Please complete the following information. DO NOT say "latest" — as soon as there's an update to anything, we won't know what version you were using. -->

 - OS and Version: <!-- e.g. macOS 10.9, Ubuntu Linux 20.04 -->
   - Installation Method: <!-- e.g. installer, source, app, snapcraft, .deb, .rpm -->
 - Mailspring Version: <!-- e.g. 1.6.2 (found in the app's menu). -->

4 posts were merged into an existing topic: White Screen of Death