While there are some browser limitations associated with IE (see below)
This link refers to several issues with IE where we recommend using a different browser.
Given that other browsers do not have this issue, would it be an option to use another browser?
One other recommendation is to run IE11 as an Administrator users have reported better performance that way.
Please verify whether the user has set “Auto refresh pausing” option changed to ON in BPPM Operations Console. If not, have them set it to ON and the performance will likely improve.