removeRLParameter.js

function removeURLParameter(url, parameter) {
    //prefer to use l.search if you have a location/link object
    var urlparts= url.split('?');
    if (urlparts.length>=2) {
        var prefix= encodeURIComponent(parameter)+'=';
        var pars= urlparts[1].split(/[&;]/g);

        //reverse iteration as may be destructive
        for (var i= pars.length; i-- > 0;) {
            //idiom for string.startsWith
            if (pars[i].lastIndexOf(prefix, 0) !== -1) {
                didRemoveURLParameter = true;
                pars.splice(i, 1);
            }
        }

        url= urlparts[0] + (pars.length > 0 ? '?' + pars.join('&') : "");
        return url;
    } else {
        return url;
    }
}

// We want to remove the `rl` parameter from the URL if it is present so that the RedirectURL is properly handled.
// This also allows us not to rely on forcing users to come to the form(s) via formula - url fields, which allows for more native navigation of the apps.
var url = window.location.href,
    didRemoveURLParameter = false,
    urlParams = new URLSearchParams(window.location.search),
    cleanedURL = removeURLParameter(url, "rl");

// Check to make sure we are editing the record
var isEditing = false;
if(urlParams.has("a") && urlParams.get("a") == "er") isEditing = true;

if(didRemoveURLParameter && isEditing) window.location.replace(cleanedURL, false);