I am trying to configure my teamcity pipeline such that builds are only triggered when a PR for a feature/* branch is targeting the master branch, but I am unable to make it work.

In my VCS Root I’ve configured my default branch => refs/heads/master then default branch specification is +:refs/pull/*/merge I’ve also tried

    +:refs/pull/*/merge 
    +:refs/heads/feature/*

VCS Root configuration

then I’ve configured a VCS Trigger with rule to ‘Trigger Build’ for all files ‘**’ using the attached VCS Root for this build pipeline. the Branch filder is

   +:feature/*
   +:pull/*/merge

also tried

   +:refs/heads/feature/*
   +:ref/pull/*/merge

VCS Trigger configuration

Teamcity version is “2023.05.6”

What I want to mention is that the pipeline does not trigger, using this configuration.
However if I in the VCS Root configure Branch Specification to refs/heads/* it triggers, but it triggers not only on PR , but every time I push a new branch , or changes to existing branch.