Tab Groups with Panorama View Add-on for Firefox 57+

https://addons.mozilla.org/en-US/firefox/addon/panorama-view/

• Create and remove groups
• Drag and drop tabs between groups

• More solid thumbnailing
• Double checking that the active group in a window is always set and valid
• Fix up renaming of groups
• Backups (Waiting for API) Import works, but creating windows and tabs correctly isn't really possible right now (can't open about: urls, etc)

• Different views of the groups
  • Automatic with thumbnails
  • Manually resizable/movable groups with thumbnails (set tab view type per group (thumbnails, list))
  • List view with vertical lists (scrollable)
• Dark theme
• Make new group and set active when you delete last group in a window
• Drag and drop tabs and groups between windows (maybe)

• Tab and tab-strip hiding (coming in v59)
• Import/restore backup

• Properly open backup urls (maybe)

• Attached tab isn't added
• Detached tab not always removed