After upgrade from 14.5 GA to 14.5 SP1 CHF1 you have noticed that users opening Identity Portal User page see white screen or it looks like page is not loading.
Identity Portal 14.X
Stale temporary data in browser.
Since page is loading fine in incognito mode or different browser the solution is to delete temporary files.
For example Chrome - Delete Browsing Data - time range pick "All time" - select "Cached images and files"