Expanding the List v3 filters pane in IE11 is extremely slow on tables with large amounts of related listsDescriptionIn Istanbul and later releases, List v3 offers the ability to query tables based on their related tables contents, using the new Related List Conditions section.On tables that have a large number of relationships, the opening of the filters pane in IE11 is extremely slow. For example, on the sys_user table it takes more than 10 seconds for the interface to become usable again after pressing the filter icon. This is due to: the large number of reference fields that point toward the sys_user tablethe 4000+ references that need to display in the Related List Conditions dropdown for the sys_user table During the freeze time, you will likely receive an alert that states "service-now.com is not responding."Performance in Chrome and Firefox is acceptable. These two browers manage the mass update of the DOM with 4000+ relationships more efficiently.Steps to Reproduce Ensure that you have the following installed on your instance: Istanbul Patch 3 with demo dataList v3 plugin Open Internet Explorer 11.Log in to the instance.Navigate to User Administration > Users.Click the filter icon to expand the filter pane.Note that the pane: takes an excessive time to load (for example, longer than 10 seconds)if using an IE11 virtual machine on a Mac, the cooling fan on the computer will start running at full speedwhen inspecting in the F12 Developer tools, an excessive amount of time is spent doing "Style Calculation"a request happens in the background to the URL "/api/now/ui/related_list/related/sys_user/all" that contains 4000+ resultsWorkaroundAfter carefully considering the severity and frequency of the issue, and the cost and risk of attempting a fix, it has been decided to not address this issue in any current or near future releases. We do not make these decisions lightly, and we apologize for any inconvenience. As a workaround, disable List v3 on the specific affected list for users and groups. This avoids the list pulling the bigger amount of data for v3, that IE does not handle without tending to crash. Related Problem: PRB881008