> Filename extensions are usually hidden in macOS, but if you find them useful, you can show them. https://support.apple.com/guide/mac-help/show-or-hide-filena

> Filename extensions are usually hidden in macOS, but if you find them useful, you can show them. https://support.apple.com/guide/mac-help/show-or-hide-filename-extensions-on-mac-mchlp2304/mac https://support.apple.com/guide/mac-help/show-or-hide-filena... (This matches my experience. Perhaps you simply forget changing this setting.)