Why commands copied from websites break

“Unknown option –save”? “Invalid character”? Blogs and AI chats quietly corrupt commands. Here’s what happens and how to fix it.

2 min4 stepsmacOS · Linux · Windows

1
The double hyphen became a dash
Word processors and blogs turn -- into an en dash (–). The shell sees an unknown option.
$npm install –save-dev prettier
```
npm error code EUSAGE
npm error Unknown command: "–save-dev"
```
2
Quotes turned curly
Curly quotes “like these” aren’t quotes to a shell or compiler.
$echo “hello”
```
“hello”
```
Invisible spaces sneak in
Non-breaking spaces from web pages look normal but break commands and indentation.
The fix
Paste any command into the ClepBoard cleaner with the Code preset: dashes, quotes and invisible characters are repaired. Every command in this library is already clean.

The double hyphen became a dash