You can customize the dragging preview with cdkDragPreview
directive, described in Angular Materials D&D CdkDragPreview docs.
<div cdkDropList class="example-list" (cdkDropListDropped)="drop($event)">
<div class="example-box" *ngFor="let movie of movies" cdkDrag>
{{movie.title}}
<img *cdkDragPreview [src]="movie.poster" [alt]="movie.title">
</div>
</div>
See example Stackblitz.
For your example you can add an element into your cdkDrag
root element.
E.g.:
...
<tr *ngFor="let feed of todo;let index = index" cdkDrag (cdkDragStarted)="started($event)">
<span *cdkDragPreview>Test</span>
<td>
...
Check your adapted Stackblitz.
.cdk-drag-preview
class activated. And when you release item,.cdk-drag-animating
class activated. Change.cdk-drag-preview
display property to none. – Sadaf Niknam