It's great to see non-printable characters but it would be better if, like in IntelliJ IDEA, we could only see the white spaces, and not the carriage returns. Maybe a more finegrained piece of functionality, where the user can select exactly which non-printable characters they want to see.
IMHO, it should be an extra section in Editor Preferences, maybe below "When Saving Files". I'm thinking multiple checkboxes, selecting what kind of "non-whitespace" I want to see then "View > Show non-Printable" is selected: Whitespace, Tabs, CR, CRLF*, others.
* When dealing with teams composed by a mix of Linux/Windows users, it's important to know if they created the file with CR or CRLF. In VIM, I can see a "^M".
This old bug may not be relevant anymore. If you can still reproduce it in 8.2 development builds please reopen this issue.
Thanks for your cooperation,
NetBeans IDE 8.2 Release Boss