TL;DR
Standard Users can always Tab-To-Enter
This isn't a specific PC Workstation Problem, it comes and goes
In our environment (1903 x64 Pro) we have roaming profiles and I can report that a standard user (read not administrator), may be able to use the UI interface correctly on PC-A, then roam to PC-B and be unable to use the UI. Tab-to-Enter will work for them regardless of which PC they are logged into, however none of my users are savvy enough to learn this (we always have to remote in and tab for them). We've also seen them roam back to PC-A, and the UI now doesn't work, then roam to PC-C and it does again. It's very hit or miss all over the place. Each PC workstation in our environment is for all concerns identically configured and running the same software and versions of said software.