Closes #6735

Changes proposed in this pull request:

• fixed: line height of left handside feed navigation
• fixed: css map comment
• improved (similar to Improve aside feed bar #6446): hovering area over the drop down category icon is now bigger

How to test the feature manually:

1. see the feed navigation in normal view
2. hover over the icons and categories
3. see the icon while hovering

Pull request checklist:

• clear commit messages
• code manually tested