WIP: 40

See: https://blogs.gnome.org/shell-dev/2020/12/18/gnome-shell-ux-plans-for-gnome-40/

Warning: this is unfinished work and the current state may not represent the final release

TODO:

• Workspaces
  • Make them horizontal
  • Drag n' Drop behavior
  • Add hover state to workspaces
  • Figure out the click interaction
  • 3 workspaces by default
  • Shadow and rounded corner
• Dash
  • Make it horizontal
  • Move to the bottom
• App Grid
  • Make it horizontal
  • Improve Drag n' Drop behavior
• Overview
  • Merge app grid and workspaces pages
  • Add adjustment to control transition
  • Hook swipe tracker to adjustment
  • Merge ViewSelector and ControlsManager
  • Make the search page an overlay
  • Interpolate final states
  • Use 3-finger to trigger the swipe
• Gestures
  • Introduce the overview gesture
  • Review and land !1326 (merged)
  • Share the same adjustment between WorkspacesDisplay and WorkspaceAnimation
  • Fix 3fg confusing secondary monitor workspaces
  • Fix changing workspaces when dragging the app grid
• Others
  • Fix keyboard navigation
  • Fix workspaces in session mode miscalculate the window clones sizes
  • List and fix regressions