Notification banners stay open forever

**Describe the bug**
When performing actions, you get a notification banner in the top right corner.
Previously, these banners stayed there for a few seconds, then faded away automatically.
But recently, this has changed, so that the banners stay on the screen forever, and have to be manually closed.
This is quite annoying, especially if you perform many (cleanup) operations.

**To Reproduce**
Steps to reproduce the behavior:
1. Perform any action, like 'Profile | Check for updates'
2. See that the banner stays forever, until the app is closed

**Expected behavior**
A notification banner should only stay open for some seconds, then fade away automatically.

**Screenshots**

**Logs(Click profile > View Logs > app.log, client.log)**
n/a

**Version (please complete the following information):**
- OS: Windows
- Version 2.12.1-stable.574