To single spaces

`Ctrl` + `Space`

All hotkeys for Scrivener 1.9.9

Documents Move item up	`Ctrl` + `↑`
Documents Remove item	`↑ Shift` + `Del`
Documents Duplicate item with subdocuments	`Ctrl` + `↓`
Documents Move item left	`Ctrl` + `←`
Documents Move item right	`Ctrl` + `→`
Documents Split at the selection	`Ctrl` + `K`
Documents Split with selection as name	`Ctrl` + `↑ Shift` + `K`
Documents Set selection as name	`F2`
Documents Duplicate item without subdocuments	`Ctrl` + `↑ Shift` + `D`
Documents Take a snapshot	`Ctrl` + `5`
Documents Take a snapshot with name	`Ctrl` + `↑ Shift` + `5`
Documents Open in editor	`Ctrl` + `↑ Shift` + `⤶ Enter`
Documents Open in other editor	`Ctrl` + `Alt` + `⤶ Enter`
Documents Open in external editor	`Ctrl` + `F5`
Documents Group selection	`Ctrl` + `G` then `Ctrl` + `U`
Documents Ungroup selection	`Ctrl` + `↑ Shift` + `U`
Documents Merge documents	`Ctrl` + `M`
Editing Add current to completions	`Ctrl` + `G` then `Ctrl` + `A`
Editing Show spelling	`Ctrl` + `G` then `Ctrl` + `Q`
Editing Insert image	`Ctrl` + `G` then `Ctrl` + `J`
Editing Insert current date and time	`Ctrl` + `F6`
Editing Project search	`Ctrl` + `G` then `Ctrl` + `S`
Editing Undo	`Ctrl` + `Z`
Editing Redo	`Ctrl` + `Y`
Editing Cut	`Ctrl` + `X`
Editing Copy	`Ctrl` + `C`
Editing Paste	`Ctrl` + `V`
Editing Select all	`Ctrl` + `A`
Editing Find dialog	`Ctrl` + `F`
Editing Find next	`F3`
Editing Find previous	`↑ Shift` + `F3`
Editing Replace and find next	`Ctrl` + `H`
Editing Paste and match style	`Ctrl` + `↑ Shift` + `V`
Editing Find by format dialog	`Ctrl` + `F3`
Editing Find next by format	`Ctrl` + `↑ Shift` + `F3`
Editing Find previous by format	`Ctrl` + `Alt` + `F3`
Editing Complete current word	`Alt` + `=`
Editing Complete current title	`Ctrl` + `G` then `Ctrl` + `M`
File New project	`Ctrl` + `G` then `Ctrl` + `N`
File Open project	`Ctrl` + `O`
File Page setup	`Ctrl` + `↑ Shift` + `P`
File Print	`Ctrl` + `P`
File Print preview	`Ctrl` + `G` then `Ctrl` + `R`
File Close project	`Ctrl` + `F4`
File Save	`Ctrl` + `S`
File Save as	`Ctrl` + `↑ Shift` + `S`
File Compile	`Ctrl` + `↑ Shift` + `E`
File Import files	`Ctrl` + `↑ Shift` + `J`
File Import web page	`Ctrl` + `↑ Shift` + `W`
File Export files	`Ctrl` + `↑ Shift` + `X`
Formatting Underlined	`Ctrl` + `U`
Formatting Toggle typewriter scrolling	`Ctrl` + `G` then `Ctrl` + `T`
Formatting Toggle ruler	`Ctrl` + `↑ Shift` + `R`
Formatting Toggle invisibles	`Ctrl` + `↑ Shift` + `\`
Formatting Toggle ghost notes	`Ctrl` + `↑ Shift` + `7`
Formatting To title case	`Ctrl` + `6`
Formatting To straight quotes	`Ctrl` + `↑ Shift` + `
Formatting To smart quotes	`Ctrl` + `
Formatting To single spaces	`Ctrl` + `Space`
Formatting Super script	`Ctrl` + `G` then `Ctrl` + `↑`
Formatting Sub script	`Ctrl` + `G` then `Ctrl` + `↓`
Formatting Strike through	`Ctrl` + `↑ Shift` + `-`
Formatting Single line spacing	`Ctrl` + `↑ Shift` + `1`
Formatting Single half line spacing	`Ctrl` + `↑ Shift` + `3`
Formatting Shrink font	`Ctrl` + `<`
Formatting Enlarge font	`Ctrl` + `>`
Formatting Show citations	`Ctrl` + `G` then `Ctrl` + `O`
Formatting Script writing	`Ctrl` + `4`
Formatting Script elements popup	`Ctrl` + `\`
Formatting Paste ruler	`Ctrl` + `G` then `Ctrl` + `P`
Formatting Paste formatting	`Ctrl` + `↑ Shift` + `Y`
Formatting Outlined	`Ctrl` + `;`
Formatting Italic	`Ctrl` + `I`
Formatting Inline footnote	`Ctrl` + `↑ Shift` + `F`
Formatting Inline annotation	`Ctrl` + `↑ Shift` + `A`
Formatting Footnote	`↑ Shift` + `F5`
Formatting Fonts	`F4`
Formatting Double line spacing	`Ctrl` + `↑ Shift` + `2`
Formatting Copy ruler	`Ctrl` + `G` then `Ctrl` + `C`
Formatting Copy formatting	`Ctrl` + `↑ Shift` + `C`
Formatting Comment	`↑ Shift` + `F4`
Formatting Bold	`Ctrl` + `B`
Formatting Align right	`Ctrl` + `R`
Formatting Align left	`Ctrl` + `L`
Formatting Align justified	`Ctrl` + `J`
Formatting Align center	`Ctrl` + `E`
Only full screen Full screen go to	`Ctrl` + `G` then `Ctrl` + `G`
Other Increase text indent	`Ctrl` + `T`
Other Decrease text indent	`Ctrl` + `↑ Shift` + `T`
Other Increase left indent	`Ctrl` + `Q`
Other Decrease left indent	`Ctrl` + `↑ Shift` + `Q`
Project Toggle keywords HUD	`Ctrl` + `↑ Shift` + `O`
Project Text statistics	`Ctrl` + `/`
Project Show auto complete list	`Ctrl` + `↑ Shift` + `4`
Project Project targets	`Ctrl` + `,`
Project Project statistics	`Ctrl` + `.`
Project Edit meta data	`Ctrl` + `↑ Shift` + `M`
Project Add new text	`Ctrl` + `N`
Project Edit new text	`Ctrl` + `T` then `Ctrl` + `N`
Project Add new folder	`Ctrl` + `↑ Shift` + `N`
Tools Toggle scratch pad	`Ctrl` + `↑ Shift` + `0`
Tools Preferences	`F12`
Tools Define in WordNet	`Ctrl` + `G` then `Ctrl` + `F3`
View Zoom out	`Ctrl` + `-`
View Zoom in	`Ctrl` + `=`
View Vertical editor split	`Ctrl` + `↑ Shift` + `'`
View Toggle inspector	`Ctrl` + `↑ Shift` + `I`
View Toggle full screen	`F11`
View Toggle editor lock	`Ctrl` + `↑ Shift` + `L`
View Toggle collections	`Ctrl` + `↑ Shift` + `9`
View Toggle binder	`Ctrl` + `↑ Shift` + `B`
View Show text	`Ctrl` + `1`
View Show outliner tint	`F8`
View Show outliner	`Ctrl` + `3`
View Show index card tint	`F7`
View Show index card status	`F10`
View Show index card label	`F9`
View Show index card keywords	`Ctrl` + `F12`
View Show icon tint	`F6`
View Show corkboard	`Ctrl` + `2`
View Show binder tint	`F5`
View Rewind action	`Ctrl` + `{`
View Reveal in binder	`Ctrl` + `↑ Shift` + `8`
View Previous document	`Alt` + `↑ Shift` + `↑`
View Previous container	`Ctrl` + `↑ Shift` + `↑`
View Previous collection	`Ctrl` + `G` then `Ctrl` + `↑ Shift` + `[`
View Play / Pause action	`Ctrl` + `⤶ Enter`
View No editor split	`Ctrl` + `'`
View Next document	`Alt` + `↑ Shift` + `↓`
View Next container	`Ctrl` + `↑ Shift` + `↓`
View Next collection	`Ctrl` + `G` then `Ctrl` + `↑ Shift` + `]`
View Horizontal editor split	`Ctrl` + `+`
View Focus next major element	`Ctrl` + `⭾ Tab`
View Fast forward action	`Ctrl` + `}`
View Expand all	`Alt` + `]`
View Enclosing group	`Alt` + `↑ Shift` + `←`
View Editor selection	`Alt` + `↑ Shift` + `→`
View Current editor forward	`Ctrl` + `]`
View Current editor back	`Ctrl` + `[`
View Collapse all to current level	`Alt` + `-`
View Collapse all	`Alt` + `[`
View Alternate editor forward	`Ctrl` + `G` then `Ctrl` + `]`
View Alternate editor back	`Ctrl` + `G` then `Ctrl` + `[`