Refresher for react js

Hello, I’m trying to implement a refresher in a PWA application built on react js + material ui
As soon as I implemented refresher, I ran into such a problem that the text (text is displayed with a delay) in the content part is displayed not immediately, but with a delay
<IonContent> <IonRefresher slot="fixed" onIonRefresh={doRefresh}> <IonRefresherContent /> </IonRefresher> <main className={classes.content}>text is displayed with a delay</main> </IonContent>

this makes the .hydrated class for the html