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Your LimeSurvey version:  Version 3.28.54
Own server or LimeSurvey hosting: Limesurvey
Survey theme/template: Fruity(Custom)
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Good afternoon,

This is a multi part question.

First, with referral URL enabled, why are there blank referral URL in the responses, and what is the fix?

Second, a variable, 'id',  is used in the panel integration, is a hidden short free text, and passthrough by the URL.  It is blank too.  Is there a way to have limesurvey use POST in the URl, or is there another solution viable? Tokens would be my last resort as my panel list is 100K+

Thanks in advance!

 

Quick guess.
"id" is used by Limesurvey, the so called SAVEDID.

You should use a different code.

Joffm 

Today, the referral URL is blocked by most browsers, so this is not a Limesurvey issue, but rather a general internet issue.

Passing the http referer is optional and many browsers today don't pass it on. You can even modify it as a user in some browsers. So I wouldn't rely on the refer url in any way, because it can't be trusted.