Open message in separate preview window

`⌘ Cmd` + `O`

All hotkeys for Airmail

General Label	`L`
General Move To	`V`
General Mark as Star	`↑ Shift` + `⌘ Cmd` + `S`
General New Message	`⌘ Cmd` + `N`
General Select Next Conversation	`N`
General Select Previous Conversation	`P`
General Refresh/Get Messages	`⌘ Cmd` + `⌥ Option` + `R`
General Mark as Read	`⌘ Cmd` + `↑ Shift` + `U`
General Cancel or Extended View	`⌘ Cmd` + `.`
General Show All/Remove all filters	`0`
General Redirect	`Control` + `⌥ Option` + `⌘ Cmd` + `R`
General Send Again	`⌥ Option` + `↑ Shift` + `⌘ Cmd` + `D`
General Go to First	`⌘ Cmd` + `Home`
General Go to Last	`⌘ Cmd` + `End`
General Hide Message Detail	`⌘ Cmd` + `←`
General Show Message Detail	`⌘ Cmd` + `→`
General Set Actions	`T`
General Set Actions	`#`
General Select messages from the same sender	`=`
General Mark as Not Important	`⌘ Cmd` + `↑ Shift` + `I`
General Reply	`⌘ Cmd` + `R`
General Reply All	`⌘ Cmd` + `↑ Shift` + `R`
General Quick Reply	`⌘ Cmd` + `E`
General Quick Reply All	`↑ Shift` + `⌘ Cmd` + `E`
General To Do	`⌥ Option` + `⌘ Cmd` + `B`
General Memo	`⌥ Option` + `⌘ Cmd` + `N`
General Done	`⌥ Option` + `⌘ Cmd` + `M`
General Load Image	`⌥ Option` + `J`
General Switch Account	`Control` + `1` - `9`
General Operations	`Control` + `T`
General Attach	`↑ Shift` + `⌘ Cmd` + `A`
General Hide Hidden Folders	`⌥ Option` + `↑ Shift` + `⌘ Cmd` + `F`
General Export to email	`⌥ Option` + `⌘ Cmd` + `E`
General Copy message Link	`Control` + `⌥ Option` + `⌘ Cmd` + `C`
General Paste and Match Style	`⌥ Option` + `↑ Shift` + `⌘ Cmd` + `V`
General Paste text only	`↑ Shift` + `⌘ Cmd` + `V`
General Search All Messages	`⌘ Cmd` + `F`
General Find in Messages	`⌥ Option` + `⌘ Cmd` + `F`
General Quote Selection	`⌥ Option` + `⌘ Cmd` + `I`
General Plain text composer	`↑ Shift` + `⌘ Cmd` + `T`
General Convert to 'Reply All' while replying	`Control` + `⌘ Cmd` + `A`
General Next sender while composing	`Control` + `⌘ Cmd` + `S`
General Next signature while composing	`Control` + `⌘ Cmd` + `I`
General Open message in separate preview window	`⌘ Cmd` + `O`
General Show Raw Source	`⌥ Option` + `⌘ Cmd` + `U`
General Zoom in	`⌘ Cmd` + `+`
General Zoom out	`⌘ Cmd` + `-`
General Reset Zoom	`⌘ Cmd` + `0`
General Switch to plain text	`Control` + `⌥ Option` + `⌘ Cmd` + `V`
General Show Unread	`1`
General Show Starred	`2`
General Show Attachments	`3`
General Show Conversations	`4`
General Sort by Sender	`5`
General Sort by Subject	`6`
General Sort by Replied	`7`
General Sort by Unread	`8`
General Sort by Date	`9`
General Show messages from the same sender	`Control` + `F`
General Reverse Order	`⌥ Option` + `↑ Shift` + `⌘ Cmd` + `I`
General Fantastical	`Control` + `⌥ Option` + `F`
General Show/Hide Accounts	`⌥ Option` + `⌘ Cmd` + `↓`
General Hide Folders	`⌥ Option` + `⌘ Cmd` + `←`
General Show Folders	`⌥ Option` + `⌘ Cmd` + `→`
General Calendar	`Control` + `⌥ Option` + `C`
General Reminders	`Control` + `⌥ Option` + `R`
General BusyCal	`Control` + `⌥ Option` + `Y`
General Fantastical2	`Control` + `⌥ Option` + `S`
General Omnifocus	`Control` + `⌥ Option` + `O`
General Things	`Control` + `⌥ Option` + `T`
General 2Do	`Control` + `⌥ Option` + `H`
General Find All Folders	`↑ Shift` + `⌘ Cmd` + `L`
General Show Folder Filter	`Control` + `⌘ Cmd` + `L`
General New Folder	`↑ Shift` + `⌘ Cmd` + `N`
General Delete Empty trash	`Control` + `⌥ Option` + `⌘ Cmd`
General All inboxes	`↑ Shift` + `⌘ Cmd` + `↑`
General Next Account	`Control` + `⌘ Cmd` + `→`
General Previous Account	`Control` + `⌘ Cmd` + `←`
General Show Plugins Folders	`Control` + `⌘ Cmd` + `P`
General Rules	`Control` + `⌘ Cmd` + `R`