Replace all non alphanumeric characters, new lines, and multiple white space with one space
Be aware, that \W leaves the underscore. A short equivalent for [^a-zA-Z0-9] would be [\W_]
text.replace(/[\W_]+/g," ");
\W is the negation of shorthand \w for [A-Za-z0-9_] word characters (including the underscore)
Example at regex101.com
Jonny 5 beat me to it. I was going to suggest using the \W+ without the \s as in text.replace(/\W+/g, " "). This covers white space as well.