Seems to be a known issue with Chrome:
This is a currently known problem with snapping Chrome windows in Windows 10, and you can add a STAR to the following issue to be notified of updates to bug fixing:
https://code.google.com/p/chromium/issues/detai... - UI stops updating when multiple Chrome windows are snapped to the left/right in Windows 10
I think some workarounds include dragging the snapped window back into windowed mode, or installing a theme for the Chrome windows.