3DDinosaur

Local View Manager is a Blender add-on by 3DDinosaur that lets you toggle, remove, add and recover to Local View from both the Outliner and the Viewport, complementing Blender's native Local View handling.

Theme Tamer is a Blender add-on for creating and editing themes. It lets you search, auto-group and batch-edit theme properties, then save the result as a Blender theme.