to get the smart break (break-word) work well on different browsers, what worked for me was the following set of rules:
#elm {
word-break:break-word; /* webkit/blink browsers */
word-wrap:break-word; /* ie */
}
-moz-document url-prefix() {/* catch ff */
#elm {
word-break: break-all; /* in ff- with no break-word we'll settle for break-all */
}
}