Dear Syncfusion Team,
This bug is not 'visible per se' - but casues a lot of issues in our implementation of Kanban.
(it is visible, as we have refresh callback after closing the dialog, which then is taking selectionArray as the source of truth - and after closing the dialog and refreshing the data - multiple cards are selected, instead of one - because of bug in your code).
When double click is triggered seems that it adding twice Id in actionModule.selectionArray (same as data) - so once for cardClick, and ducplicated in cardDoubleClick.
you can see it when you doubleClick on very simple stackBlitz example (console logging internal state of array)
https://stackblitz.com/edit/github-4jnupv?file=src%2Fapp.component.ts
I will apply workaround and remove duplicated id myself - in cardDoubleClick handler, but please fix it also on your side.