When running Chrome as a windows credential provider, it needs to run the gpu process in an alternate desktop because the default sandbox integrity level of the gpu process (LOW) is too low to access the winlogon desktop, which requires an integrity level of MEDIUM. However, since the gpu process is running on an alternate desktop it cannot render to the winlogon desktop causing all gpu rendering to be disabled. 

To prevent this potential problem, Chrome is run with the flag --disable-gpu so that it can still render to screen correctly even without the gpu-process. If we need to enable the gpu-process in the future, further investigation will be needed. At minimum if we change the integrity level of the GPU process to MEDIUM or set a delayed integrity level (so that the process starts at MEDIUM and then later gets lowered to LOW), this will resolve the problem.