Performance Listbox - first click on "select all"

[richardaubin]

This appears to be an issue that I also recently commented on this thread, except with the RadzenCheckboxList:

Radzen Treeview - Limits

I'm also experiencing something similar with a checkboxlist... I get a random time delay between click and update on the first check only. Any subsequent checks happen instantaneously. The delay can be over a second or more at times. The delay shown happens when I click at 06:21 (when the pointer highlight expands) in the video. [Radzen checkbox click delay]