What it does

Main menu > Navigate > Symbol...

Quick way to go to a specific unique identifier directly
(e.g. all graphql-types in the graphql-service like "UserType")

Why should you use it

Searches for symbols (e.g. variables and methods) in the project

What it does

Main menu > Navigate > Line/Column...

Quick way to get to the code mentioned in a compiler/exception error message

(Note: You can also append something like ":50" to any search to instantly jump to the line in the search result)

Why should you use it

Jumps to specified line (and optionally column) in the current document

What it does

Main menu > Navigate > Next Highlighted Error

Quickest way to fix call-sites of changed functions

Why should you use it

Jumps to errors/warnings in the current document

What it does

Main menu > Navigate > Next Change

Quick way to look through your changes in a document

(especially good in large files)

Why should you use it

Jumps to (VCS) changes in the current document

What it does

Main menu > Edit > Find > Go to next highlighted element usage

Quick way to look at the usages of a variable/method

(especially good in large files)

Why should you use it

Jumps to next usage of the element at caret

What it does

Main menu > Navigate > Declaration or Usages

Quick way to trace a call-graph or look into the implementation

(also works with indexed third-party libraries!)

Why should you use it

At call-site: Jumps to declaration

At declaration: Jumps to call-site

What it does

Main menu > Navigate > Implementation(s)

Useful for jumping to the implementation from the interface method (trait)

Why should you use it

At call-site: Prompts for jump to declaration/implementations

At declaration: Jumps implementation

What it does

Main menu > Edit > Find > Show Usages

Quick way to trace the call-path backwards or to estimate impact of changing a method

Why should you use it

Jumps to the usage of method/function at caret or prompts to jump if there are multiple usages

What it does

Other > Bookmarks > Go to/Toggle bookmark <N>

Quick way to jump between functionality which is split between multiple documents or places within one large document

Why should you use it

Set and jump to bookmarked lines in documents

What it does

Main menu > View > Parameter Info

Calling a method is easier if you know what it expects

(see also: "Type Tetris", "Type Holes")

Why should you use it

Shows the expected parameters of the parameter list at caret

What it does

Main menu > View > Type Info

Helps if you're unsure whether the type of something you wrote is actually what you think it is

Why should you use it

Shows pop-up with type of selected expression

What it does

Plug-Ins > Scala > Show implicit arguments action

Very useful for finding/debugging implicit arguments or typeclasses

Why should you use it

Prompts for expressions at caret which use implicit arguments and lists those arguments (with jump to definition!)

What it does

Plug-Ins > Scala > Show implicit conversions

Helps to debug implicit conversion fuckery

Why should you use it

Prompts for expressions at caret and lists all implicit conversions in scope

What it does

Main menu > VCS > Git > Fetch

Useful to update the version control tool window without pulling

Why should you use it

Fetches tracked remote branches

What it does

Main menu > VCS > Git > Branches...

Quick way to do all sorts of git operations related to branching

Why should you use it

Prompts for git branches with most actions you can do with them

What it does

Main menu > VCS > Git > Stash/UnStash changes...

If you need to quickly do something else while working on a larger task stashing is probably the best solution

Why should you use it

Opens dialog for git stash/unstash

What it does

Main menu > VCS > Git > Show History for Selection

Incredibly useful for understanding why something was changed and who did it

Why should you use it

Shows all commits that touched the selected code

What it does

Version Control Systems > Rollback Lines

Useful for reverting current changes in (parts of) a document without accidentally leaving remnants in the commit (e.g. whitespace changes)

Why should you use it

Reverts uncommited changes of selected lines