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Hidden Files
Hidden Files lists the folders and files whose names start with a dot, which Finder does not show, largest first, and says what each known one is. Developer tools keep a lot here: package caches, virtual environments and build folders.
What it lists
Everything in the last scan whose name starts with a dot, biggest first, up to the largest 500. Only the topmost one is listed, so a hidden folder appears once rather than alongside the hidden folders inside it. Files count from 1 MB.
Things Finder hides without a dot, such as ~/Library, are not in this list.
They are in the Space Map like everything else.
What each one is
Choose a row and a note at the foot of the room says what it is, for the names Strata
knows: .Trash, .ssh, .npm, .gradle,
.cache and many more. Where it is true, the note adds that the tool which made it
rebuilds it when it needs it.
For a name it does not recognise, the note says so plainly: hidden folders are usually made by an app or a developer tool, and if you do not know which, leave it.
Some hidden folders are precious. .ssh holds the keys that
let you into servers, and a project's .git folder is its whole history. Both
are small and worth keeping. Remove a hidden folder only when you know what made it.
Counting each drive's Trash
Each drive keeps its own Trash, in a hidden .Trashes folder at its top, for what
you deleted from that drive. Tick Count each drive's Trash to include
it; the change applies from the next scan, and Scan Again is right
there. The Trash itself can never be removed from Strata: empty it in Finder, which is the one
step that cannot be undone.
Removing
The list works like Search's: tick boxes, Select All, Select None and Move to Trash…, which opens the confirmation sheet. Everything goes to the Trash.
The three different ways macOS hides files, and which hidden folders tend to grow, are explained in The files macOS does not show you.