Currently, I am upgrading the WebDriverIo version from 4 to 5 wherein one of the existing tests we are applying waitForExist on two selectors simultaneously. In v4 it's like this .waitForExist(selector + loadingSelector, null, true) But in V5 waitForExist chaining to selector and therefore I've refactored this to await (sel1+loadingSelector).waitForExist(0,true,null); but this throwing error `TypeError: (selector + loadingSelector).waitForExist is not a function

Here is my bit of command code:

addIdeCommand('ideOpenFolder', async function (folder, treeCls, fuzzy) {
    var sel1 =await browser.$(sel1);
    var loadSelector = await browser.$(sel2);
    

        await sel1.waitForDisplayed();
        // Wait for the loading icon to disappear (true = not exists)
       **await (selector+loadSelector).waitForExist(0,true,null);**
        await this.waitUntil(async function () {
            //something
        });
});

Can someone please help me with how to apply waitForExisting() on multiple selectors at the same time?