Question 1

What is an ICNS file?

Accepted Answer

ICNS is the macOS icon container format that stores multiple icon resources at different sizes.

Question 2

Why are some ICNS chunks not previewed as images?

Accepted Answer

Some chunks use legacy pixel encodings or metadata blocks that are not directly browser-decodable; raw chunk export is still available.

Question 3

は files uploaded to a server?

Accepted Answer

No. Local files are parsed in-browser. URL mode depends on source CORS permissions.

ICNS Viewer and Extractor

File メタデータ