What's Changed

Breaking Changes

• Renamed collapsed: option to start_collapsed: — using collapsed: now raises ArgumentError
  with migration instructions
• Removed backward compatibility for v2 collapsed: true API
• Minimum ActiveAdmin version is now 3.2+
• Dropped support for EOL Ruby/Rails versions

New Features

• Collapsible sidebar with vertical pill toggle button (replaces old hide/show buttons)
• Per-resource sidebar state — collapsing one resource's sidebar doesn't affect others
• start_collapsed: true option to start sidebar in collapsed state
• Sidebar state persisted in session using a single compact key

Improvements

• ActiveAdmin pages are no longer affected when no sidebar options are set
• Removed icono icon dependency — toggle button uses pure CSS chevrons
• Simplified JavaScript — chevron direction handled entirely by CSS
• Added CSS-only hover effect on toggle button
• Added animated GIF demo to README

CI & Infrastructure

• Modernized CI: GitHub Actions, Cuprite driver, SimpleCov coverage
• Added coverage badge via GitHub Pages
• Test matrix: Ruby 3.2–3.4, Rails 7.1–8.0, ActiveAdmin 3.2–3.5
• Added Sprockets manifest.js for Rails 8 compatibility

Full Changelog: v2.0.0...v3.0.0

What's Changed

• add rails v6.0 and activeadmin v2.8 to travis matrix by @gigorok in #22
• drop ruby 2.4, add ruby2.5 to travis instead by @gigorok in #23
• to remove large space after first comment by @Ivanov-Anton in #20
• bump v2.0.0 by @gigorok in #24

New Contributors

• @gigorok made their first contribution in #22
• @Ivanov-Anton made their first contribution in #20

Full Changelog: v1.2.0...v2.0.0

Contributors

• @gigorok
• @Ivanov-Anton

• Drop dependency of CofeeScript

• Compatibility with ActiveAdmin 1.4.0