Atom package to highlight bad characters such as No-break space ( ) and the Greek question mark (;) in your source files.
With this package you'll easily notice invisible and easy-to-confuse characters, which can be the cause for incredibly annoying syntax errors in source code.
Save yourself the burden of debugging invisible bugs for hours!
Versions from 2.0.0 onwards use a (user-extendable) whitelist of commonly used source code characters instead of trying to find specific bad characters using a blacklist. If this is an issue for you, check out the blacklist-based fork: highlight-bad-chars-bl