Kendo MultiColumnComboBox Lag and Freezing in any browser

[Mutasim]

Hi everyone,

We're experiencing a major performance issue with our Kendo MultiColumnComboBox when used alongside Wijmo FlexSheet like opening excel and switching between worksheets or copy pasting cell value. The dropdown becomes incredibly laggy and unresponsive, to the point of freezing the entire browser, making it practically unusable. It is only happening in this scenario. All other dropdown used like mat-select or any text input is working properly in this scenario.

Here's a breakdown of the problem:

Symptoms: Kendo MultiColumnComboBox dropdown experiences severe lag and freezing when:
1. Opening the dropdown.
2. Scrolling within the dropdown.


We've tried various solutions to improve performance, including:
Memory optimization: Tested with limited memory (2GB) to rule out memory leaks, but the issue persisted.
Virtualization: Implemented virtualization for the dropdown, but it didn't alleviate the lag.

We're at a loss and would greatly appreciate any insights or suggestions from the community. Has anyone encountered similar issues with Kendo MultiColumnComboBox and Wijmo FlexSheet integration?
What troubleshooting steps or alternative solutions would you recommend?
Thanks in advance for your help!
We're hoping to find a solution that resolves this critical performance issue and improves the user experience for our platform.