Check your Model View Option settings.
Sounds like you may have changed to an MVO scheme that shows a low level of detail for windows and railings.
You should be able to change to another MVO scheme, or reset the level of detail settings in the scheme you want to use.
Barry.
One of the forum moderators.
Versions 6.5 to 27
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11