How to remove selection highlighting for input field in JavaScript for Vive Focus Android WebView?

Question

I'm trying to disable selection highlighting and the context menu (Copy, Cut, Select All, etc.) of input fields using JavaScript on a Vive Focus VR headset Android WebView.

I've tried the below solutions, but none of them work for the Vive Focus:

Solution #1:

$.fn.extend({
    disableSelection : function() {
        this.each(function() {
            this.onselectstart = function() {
                return false;
            };
            this.unselectable = "on";
            $(this).css('-moz-user-select', 'none');
            $(this).css('-webkit-user-select', 'none');
        });
    }
});

$(function() {
    $(this).disableSelection();
});

Solution #2:

function disableSelect(el){         
    if(el.addEventListener){
        el.addEventListener("mousedown",disabler,"false");
    } else {
        el.attachEvent("onselectstart",disabler);
    }
}

function enableSelect(el){
    if(el.addEventListener){
    el.removeEventListener("mousedown",disabler,"false");
    } else {
        el.detachEvent("onselectstart",disabler);
    }
}

function disabler(e){
    if(e.preventDefault){ e.preventDefault(); }
    return false;
}

Solution #3:

window.oncontextmenu = function () {return false;};

Solution #4:

function absorbEvent_(event) {
    var e = event || window.event;
    e.preventDefault && e.preventDefault();
    e.stopPropagation && e.stopPropagation();
    e.cancelBubble = true;
    e.returnValue = false;
    return false;
}

function preventLongPressMenu(node) {
    node.ontouchstart = absorbEvent_;
    node.ontouchmove = absorbEvent_;
    node.ontouchend = absorbEvent_;
    node.ontouchcancel = absorbEvent_;
}

function init() {
    preventLongPressMenu(document.getElementById('theimage'));
}

I posted another question (How to remove selection highlighting for input field in CSS?) related to this about using CSS to achieve this, but unfortunately, it does not disable the selection/context menu on the Vive Focus for input fields.

Could you please help me with this?

Thanks