Make the sidebar's view switching UX more conventional and less buggy

2 jobs for !37 with more-conventional-sidebar in 17 minutes and 41 seconds (queued for 1 second)
detached
Status Job ID Name Coverage
  Build
passed #16656
build_ubuntu_18_04

00:11:54

passed #16655
linux kf5-qt5 qt5.12

00:17:41

40.0%