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⌥⇧1 captures an area, ⌥⇧2 a window and ⌥⇧3 the full screen. ⌥⇧⌘T copies the text in an area with its formatting, and ⌥⇧T as plain text. ⌥⇧R repeats the last area and ⌥⇧E opens your last capture in the Advanced editor. ⌥⇧L shows the corner, ⌥⇧S shows Kept for Later and ⌥⇧H shows Recent Captures. Clear Captures has no shortcut until you record one in Settings… › Shortcuts. On the island, ⏎ copies, ⌘S saves, ⌥⏎ keeps the capture for later, ⌘⏎ leaves it in the corner, ⇧⏎ copies it, leaves it in the corner and starts the next, and esc discards it to Recent Captures. ⌥⌘C copies a capture and keeps it for later.

Another app or macOS is probably using the same keys. If the Frostshot menu in the menu bar shows Shortcut conflict, open Settings… › Shortcuts: the message under each shortcut says what’s in the way, and you can record a different combination. Restore Defaults puts every shortcut back. Shortcuts need no permission.

It needs Screen Recording permission; a red dot in the Frostshot menu means it’s missing. Open Settings… › Permissions and click Grant. The first time, macOS shows its own prompt. After that, turn Frostshot on in System Settings › Privacy & Security › Screen & System Audio Recording, then reopen Frostshot when it asks.

If the switch is already on and captures still fail, which can happen after an update or a reinstall, select Frostshot in that list, remove it with the − button, then click Grant in Frostshot again.

⏎ copies a capture to the clipboard and doesn’t make a file. ⌘S, or Save on the island, saves it to Pictures › Frostshot. You can change the folder, the format (PNG or JPEG) and the file name in Settings… › Saving. If you choose a folder outside Pictures, Frostshot may ask you once to allow access to it.

Turn on Settings… › General › Redact sensitive data automatically. Every capture then comes out with emails, phone numbers, card numbers, keys and IP addresses blurred. The eye button on either bar turns it on or off for one capture; ⌫ removes one blur and ⌘Z removes them all. In the Advanced editor, ⇧⌘R finds them whenever you want. All of it runs on your Mac.

Click Advanced on the island, or press ⌥⇧E to open your last capture. Open from Clipboard in the Frostshot menu opens an image you copied elsewhere. In the editor you can crop, draw arrows, lines, shapes and text, add numbered steps, highlights, blur, a spotlight or a magnifier, and set the capture on a gradient or a landscape. Save a frame you like as a Look to reuse it in one click. ⌘K finds any tool or command.

A capture waits in one of three places, and nothing disappears until you decide. Captures you haven’t decided about wait in the corner, the stack at the bottom-right of the screen: ⌘⏎ leaves one there without copying it, and ⇧⏎ copies it, leaves it there and starts the next. The corner holds up to 30 captures with their annotations still editable, and they are still there after you quit; you can turn that off in Settings… › Captures. It folds into a small tile and opens sideways when you point at it or press ⌥⇧L.

Kept for Later is the list in the notch for captures you chose to keep. Press ⌥⏎ to keep one, or ⇧⌥⏎ to keep every capture in the corner, and open the list with ⌥⇧S or with Kept for Later… in the Frostshot menu. It never expires and has no limit: a capture stays until you finish it or remove it.

Recent Captures is the automatic history. What you copy with ⏎, discard with esc or clear goes there, and so does whatever you finish or remove from Kept for Later. Open it with ⌥⇧H or from the Frostshot menu in the menu bar. Click a capture to put it back in the corner, ⌘-click to copy it, ⌥-click to open it in the Advanced editor. By default it keeps 7 days and up to 50 captures, whichever limit comes first; Settings… › Captures offers 1, 7 or 30 days and 10, 25, 50 or 100 captures, or turns it off.

Quit it (Frostshot menu › Quit Frostshot), then drag Frostshot from Applications to the Trash. Captures you saved stay in Pictures › Frostshot until you delete them. To remove its settings and the captures it keeps (in the corner, in Kept for Later and in Recent Captures) as well, choose Go › Go to Folder… in Finder, enter ~/Library/Containers, and move the Frostshot folder to the Trash. You can also remove Frostshot from System Settings › Privacy & Security › Screen & System Audio Recording.