Sometimes users may see 'flashing' or 'flickering' Windows Desktop icons when using Remote Desktop (RDS) connections.
Basically, this issue occurs in remote Desktop sessions when a significant number of certain types of icons (such as PDF) are stored on a user's Desktop. Windows constantly updates these icons to facilitate the display of changes (motion, previews) in dynamic icons.
The solution is to tell Windows to just display the icons as 'icons'.
To stop the 'flashing', select the checkbox for:
File Explorer → View (tab) → Options → View (tab) → Always show icons, never thumbnails