Backport userId to overwrite visitorId feature (#16226)

* Backport userId to overwrite visitorId feature

* fix ui test

1 files changed, 3 insertions, 1 deletions

diff --git a/plugins/CoreHome/Tracker/VisitRequestProcessor.php b/plugins/CoreHome/Tracker/VisitRequestProcessor.php
index 30c5d0fd3a..b7875e087a 100644
--- a/plugins/CoreHome/Tracker/VisitRequestProcessor.php
+++ b/plugins/CoreHome/Tracker/VisitRequestProcessor.php
@@ -17,6 +17,7 @@ use Piwik\Tracker\Cache;
 use Piwik\Tracker\Request;
 use Piwik\Tracker\RequestProcessor;
 use Piwik\Tracker\Settings;
+use Piwik\Tracker\TrackerConfig;
 use Piwik\Tracker\Visit\VisitProperties;
 use Piwik\Tracker\VisitExcluded;
 use Piwik\Tracker\VisitorRecognizer;
@@ -189,7 +190,8 @@ class VisitRequestProcessor extends RequestProcessor
             return true;
         }
 
-        if (!$this->lastUserIdWasSetAndDoesMatch($visitProperties, $request)) {
+        if (!TrackerConfig::getConfigValue('enable_userid_overwrites_visitorid')
+            && !$this->lastUserIdWasSetAndDoesMatch($visitProperties, $request)) {
             Common::printDebug("Visitor detected, but last user_id does not match...");
             return true;
         }