[sieve][regex] Matching multiple strings in the "Received" header

[Adi Pircalabu]

On 07-05-2018 12:13, Adi Pircalabu wrote:
> 
> I'm trying to use this expression in Sieve, but for some reason the
> filter doesn't work:
> 
> require ["fileinto","regex"];
> 
> # rule:[gmail-outlook-yahoo-aol-friends]
> if header :regex "received"
> ".from.*(outbound.protection.outlook.com|.google.com|.yahoo.com|mx.aol.com)."
> {
>         fileinto "INBOX.gmail-hotmail-yahoo-aol-friends";
>         stop;
> }

Update: this works:

if header :regex "received" 
"from.*(outbound.protection.outlook.com|.google.com|.yahoo.com|mx.aol.com)"
{
         fileinto "INBOX.gmail-hotmail-yahoo-aol-friends";
         stop;
}

How should I write it to also match the space character at both the 
beginning and end of the expression?

---
Adi Pircalabu