Comment / uncomment with line comment

`Ctrl` + `/`

All hotkeys for IntelliJ IDEA (Windows, Linux)

Editing Smart code completion	`Ctrl` + `↑ Shift` + `Space`
Search and replace Search everywhere	`↑ Shift` then `↑ Shift`
Editing Show intention actions and quick-fixes	`Alt` + `⤶ Enter`
Editing Generate code	`Alt` + `Insert`
Editing Parameter info (within method call arguments)	`Ctrl` + `P`
Editing Extend selection	`Ctrl` + `W`
Editing Shrink selection	`Ctrl` + `↑ Shift` + `W`
Navigation Recent files popup	`Ctrl` + `E`
Refactoring Rename	`↑ Shift` + `F6`
General Open corresponding tool window	`Alt` + `Num 0` - `Num 9`
General Save all	`Ctrl` + `S`
General Synchronize	`Ctrl` + `Alt` + `Y`
General Toggle maximizing editor	`Ctrl` + `↑ Shift` + `F12`
General Inspect current file with current profile	`Alt` + `↑ Shift` + `I`
General Quick switch current scheme	`Ctrl` + `
General Open Settings dialog	`Ctrl` + `Alt` + `S`
General Open project structure dialog	`Ctrl` + `Alt` + `↑ Shift` + `S`
General Find action	`Ctrl` + `↑ Shift` + `A`
Debugging Step over	`F8`
Debugging Step into	`F7`
Debugging Smart step into	`↑ Shift` + `F7`
Debugging Smart step out	`↑ Shift` + `F8`
Debugging Run to cursor	`Alt` + `F9`
Debugging Evaluate expression	`Alt` + `F8`
Debugging Resume program	`F9`
Debugging Toggle breakpoint	`Ctrl` + `F8`
Debugging View breakpoints	`Ctrl` + `↑ Shift` + `F8`
Search and replace Find	`Ctrl` + `F`
Search and replace Find next	`F3`
Search and replace Find previous	`↑ Shift` + `F3`
Search and replace Replace	`Ctrl` + `R`
Search and replace Find in path	`Ctrl` + `↑ Shift` + `F`
Search and replace Replace in path	`Ctrl` + `↑ Shift` + `R`
Search and replace Select next occurence	`Alt` + `J`
Search and replace Select all occurences	`Ctrl` + `Alt` + `↑ Shift` + `J`
Search and replace Unselect occurence	`Alt` + `↑ Shift` + `J`
Editing Basic code completion	`Ctrl` + `Space`
Editing Complete statement	`Ctrl` + `↑ Shift` + `⤶ Enter`
Editing Quick documentation lookup	`Ctrl` + `Q`
Editing External doc	`↑ Shift` + `F1`
Editing Brief info	`Ctrl` + `Mouse movement`
Editing Show descriptions of error at caret	`Ctrl` + `F1`
Editing Override methods	`Ctrl` + `O`
Editing Implement methods	`Ctrl` + `I`
Editing Surround with…	`Ctrl` + `Alt` + `T`
Editing Comment / uncomment with line comment	`Ctrl` + `/`
Editing Comment / uncomment with block comment	`Ctrl` + `↑ Shift` + `/`
Editing Context info	`Alt` + `Q`
Editing Reformat code	`Ctrl` + `Alt` + `L`
Editing Optimize imports	`Ctrl` + `Alt` + `O`
Editing Auto-indent line(s)	`Ctrl` + `Alt` + `I`
Editing Indent selected lines	`⭾ Tab`
Editing Unindent selected lines	`↑ Shift` + `⭾ Tab`
Editing Cut current line to clipboard	`Ctrl` + `X`
Editing Cut current line to clipboard	`↑ Shift` + `Del`
Editing Copy current line to clipboard	`Ctrl` + `C`
Editing Copy current line to clipboard	`Ctrl` + `Insert`
Editing Paste from clipboard	`Ctrl` + `V`
Editing Paste from clipboard	`↑ Shift` + `Insert`
Editing Paste from recent buffers	`Ctrl` + `↑ Shift` + `V`
Editing Duplicate current line	`Ctrl` + `D`
Editing Delete line at caret	`Ctrl` + `Y`
Editing Smart line join	`Ctrl` + `↑ Shift` + `J`
Navigation View source	`Ctrl` + `⤶ Enter`
Editing Start new line	`↑ Shift` + `⤶ Enter`
Editing Toggle case for word at caret or selected block	`Ctrl` + `↑ Shift` + `U`
Editing Select till code block end / start	`Ctrl` + `↑ Shift` + `[`
Editing Select till code block end / start	`Ctrl` + `↑ Shift` + `]`
Editing Delete to word end	`Ctrl` + `Del`
Editing Delete to word start	`Ctrl` + `⬅ Backspace`
Editing Expand code block	`Ctrl` + `Num +`
Editing Collapse code block	`Ctrl` + `Num -`
Editing Expand all	`Ctrl` + `↑ Shift` + `Num +`
Editing Collapse all	`Ctrl` + `↑ Shift` + `Num -`
Editing Close active editor tab	`Ctrl` + `F4`
Refactoring Copy	`F5`
Refactoring Move	`F6`
Refactoring Safe delete	`Alt` + `Del`
Refactoring Refactor this	`Ctrl` + `Alt` + `↑ Shift` + `T`
Refactoring Change signature	`Ctrl` + `F6`
Refactoring Inline	`Ctrl` + `Alt` + `N`
Refactoring Extract method	`Ctrl` + `Alt` + `M`
Refactoring Extract variable	`Ctrl` + `Alt` + `V`
Refactoring Extract field	`Ctrl` + `Alt` + `F`
Refactoring Extract constant	`Ctrl` + `Alt` + `C`
Refactoring Extract parameter	`Ctrl` + `Alt` + `P`
Navigation Go to class	`Ctrl` + `N`
Navigation Go to file	`Ctrl` + `↑ Shift` + `N`
Navigation Go to symbol	`Ctrl` + `Alt` + `↑ Shift` + `N`
Navigation Go to previous / next editor tab	`Alt` + `← →`
Navigation Go back to previous tool window	`F12`
Navigation Go to editor (from tool window)	`Esc`
Navigation Hide active or last active window	`↑ Shift` + `Esc`
Navigation Go to line	`Ctrl` + `G`
Navigation Navigate back/ forward	`Ctrl` + `Alt` + `← →`
Navigation Navigate to last edit location	`Ctrl` + `↑ Shift` + `⬅ Backspace`
Navigation Select current file or symbol in any view	`Alt` + `F1`
Navigation Go to declaration	`Ctrl` + `B`
Navigation Go to declaration	`Ctrl` + `Mouse left click`
Navigation Go to implementation(s)	`Ctrl` + `Alt` + `B`
Navigation Open quick definition lookup	`Ctrl` + `↑ Shift` + `I`
Navigation Go to type declaration	`Ctrl` + `↑ Shift` + `B`
Navigation Go to super-method/ super-class	`Ctrl` + `U`
Navigation Go to previous /next method	`Alt` + `↑ ↓`
Navigation Move to code block end	`Ctrl` + `]`
Navigation Move to code block start	`Ctrl` + `[`
Navigation File structure popup	`Ctrl` + `F12`
Navigation Type hierarchy	`Ctrl` + `H`
Navigation Method hierarchy	`Ctrl` + `↑ Shift` + `H`
Navigation Call hierarchy	`Ctrl` + `Alt` + `H`
Navigation Next highlighted error	`F2`
Navigation Previous highlighted error	`↑ Shift` + `F2`
Navigation Edit source	`F4`
Navigation Show navigation bar	`Alt` + `Home`
Navigation Toggle bookmark	`F11`
Navigation Toggle bookmark with mnemonic	`Ctrl` + `F11`
Navigation Go to numbered bookmark	`Ctrl` + `Num 0` - `Num 9`
Navigation Show bookmarks	`↑ Shift` + `F11`
Compile and run Make project	`Ctrl` + `F9`
Compile and run Compile selected file, package or module	`Ctrl` + `↑ Shift` + `F9`
Compile and run Select configuration and run	`Alt` + `↑ Shift` + `F10`
Compile and run Select configuration and debug	`Alt` + `↑ Shift` + `F9`
Compile and run Run	`↑ Shift` + `F10`
Compile and run Debug	`↑ Shift` + `F9`
Compile and run Run context configuration from editor	`Ctrl` + `↑ Shift` + `F10`
Usage search Find usages	`Alt` + `F7`
Usage search Find usages in file	`Ctrl` + `F7`
Usage search Show usages	`Ctrl` + `Alt` + `F7`
VCS / Local history Commit project to VCS	`Ctrl` + `K`
VCS / Local history Update project from VCS	`Ctrl` + `T`
VCS / Local history Push commits	`Ctrl` + `↑ Shift` + `K`
VCS / Local history "VCS" quick popup	`Alt` + `
Live Templates Surround with Live Template	`Ctrl` + `Alt` + `J`
Live Templates Insert live template	`Ctrl` + `J`