I wasn't able to reproduce the issue in our online demo:
Please keep in mind that increasing the number of resources drastically increases the volume of html rendered on the page, and it's up to the browser to handle it. If the issue is caused by the number of events loaded in the scheduler, I would advise using the approach from the following thread to reduce the loaded items:
If the issue is related only to the number of resources and days displayed at once in the Scheduler, you would need to either show only several resources at a time, or use a view with fewer days displayed at once (DayView for instance).
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