import truncator from 'text-truncator'

...

const stopTruncator = truncator({
  sourceNode: "h3", // Required! Use CSS selectors (string) or HTML element
  sourceAncestor: ".parentDiv", // Use CSS selectors (string) or HTML element. By default it uses "body"
  ending: "read mode...",  // Use CSS selectors (string) or HTML element. By default it uses ...
  options: {
    maxLength: 700, // The maximum number of letters that we want to be shown before truncate. By default it uses Infinity
    minCutLength: 100, // The maximum number of letters after which the text completely disappears. By default it uses 0
    delay: 250, // Time (in millisec) to delay animation of truncate. Inside itself truncator uses the throttling function. By default it uses 100
    once: true // Needs to call truncator just one time without adding listener to resize event. By default it equals false
  }
});

...
useEffect(() => {
  ...
  return () => {
    stopTruncator()
    ...
  }
})
...