Hi Prince,
I am replying to this thread as I am experiencing the same issue. Selecting items (without checkboxes in my case) does not work in IE only. Chrome and FF are working correctly.
I have checked your demo you linked to and it also doesn't work (at least not every time). In my case I am able to select items with keyboard cursor + enter, but not with the mouse.
My environment:
IE ver. 11.0.9600.18793
Library version: "@syncfusion/ej2-vue-dropdowns": "^18.1.43" (installed per package-lock.json: "version": "18.1.46")
I do not see any error in the console, nor is the debugger pausing on even a caught exception. After clicking an item the dropdown is closed but no item is added to the selection.
Please review the situation.
Thank you
Tomasz