Bug report

If the CurrentTimeMarker is enabled (it is by default), the resources are grouped, and events with different resource values (about 70) are loaded for the current day, a significant performance deterioration is observed.
With the CurrentTimeMaker disabled or the events loaded for a date different than today (past or future) the performance issue is not exhibited.

Reproduction of the problem

MVCSchedulerCurrentTimeMarker.zip

1. Run the attached sample project.

Current behavior

No exceptions are thrown, but the Scheduler becomes unresponsive.

Expected/desired behavior

There should be no performance hit, regardless of CurrentTimeMarker being enabled/disabled.

Environment

• Kendo UI version: 2019.3.917
• jQuery version: x.y
• Browser: [all]