"Wechat official account developer Yuansheng return button problem

developed in Wechat official account, listening returned event page B is listening page
C page without adding listening event
page flow AME-> BMY-> C
when you click on Wechat"s official account to return, Clam-> flashed BMIT-> A will jump twice
this is Wechat"s official account listening code:

function backHistory(backUrl) {  
    let state = {  
        title: "title"  
    };  
    window.history.pushState(state, state.title, window.location.href);  
    window.addEventListener("popstate", function(e) {  //
        if(backUrl == undefined) {
            history.go(-1);
        } else {
            if(backUrl == "home") {
                if(wx != undefined) {
                    wx.closeWindow();
                }
            } else {
                location.href=backUrl;  //
            }
        }
    }, false); 
}

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