On the mobile portal view, clicking the header icon in the additional actions hamburger menu, this does not collapse as expected by the mobile user.
Steps to Reproduce
1. Login a demo instance in mobile view.
2. Open the main /sp service portal page.
3. Click on the 'Additional actions' hamburger contextual menu in the top right corner.
4. Click on the header logo.
Observe the home page will load, but the header menu does not collapse, also when clicking on few links from the menu.
This behaviour was initially by design, and has been identified as an enhancement targeted to be fixed in a future release. You can Subscribe to this article to receive notifications when more information will become available.
Related Problem: PRB1264750