Clicking on Advanced Search in IT-shop takes 15 minutes before simple filter dialog is shown

In the IT-shop I'm going to Request History. When I click on the link 'Advanced Search' it takes about 15 minutes to show a simple dialog. In the dialog its possible to set search filters. For example the 'Requests submitted by me for others' is a very useful filter to enable in this dialog. 

In the browser console log I see the following message and I think it might be the cause for this behavior. 

imx: Debug ignoring multiple action call due to isProcessing flag 

During 'Loading content' this message appears up to 18 times in the browser console log. 

Running One Identity Manager application version: 8.1 2019-01-21-229. Running It-shop on https

My question is: Why does it take so long to show this dialog?