Chartjs-How to keep rounded bar corners when data is filtered chartJs?

You already have check to apply rounded corners when not hidden (filtered).
Just need to add condition to apply rounded corners when filtered assuming that zeros are not shown.

Something like this:

if (!this._chart.getDatasetMeta(findLast).hidden) {
    lastVisible = findLast;
    if (this._chart.data.datasets[findLastTo - 1].data[this._index] == 0) {
        lastVisible -= 1;
    }
} else {
    if (this._chart.data.datasets[findLast].data[this._index] == 0) {
        lastVisible = findLast;
        lastVisible -= 1;
    }
}

Here is modified JSFiddle: https://jsfiddle.net/xopr36g5/

I fixed this problem by calculating the depth of dataset dynamically.Thanks for answers

 var lastVisible;
  var datasetsLength = this._chart.data.datasets.length;
  this._chart.data.datasets.map((e,index)=>{
    lastVisible=datasetsLength-1;
    //to find the depth of datasets and get non-zero value
    for(var i=lastVisible;i>0;i--){
    if(!this._chart.getDatasetMeta(i).hidden){
      if(this._chart.data.datasets[i].data[this._index] != 0){
        lastVisible = i;
        break;
      }
    }
    } 
  })