Civilization 4 vanilla - landscape disappears when worldwonder is finished (3900)

Compatibility Report

• Name of the game with compatibility issues: Civilization IV
• Steam AppID of the game: 3900

System Information

• GPU: Quadro K4000M

• Driver/LLVM version: nvidia 390.87

• Kernel version: 4.15.0-38-generic

• Link to full system information report as Gist: https://gist.github.com/Lalarian/63a8bbc615226ebc43e03cce8a73da2c

• Proton version: 3.7-8 and 3.7-8beta and 3.16-4beta

I confirm:

• [ x] that I haven't found an existing compatibility report for this game.
• [ x] that I have checked whether there are updates for my system available.

steam-3900.log

Symptoms

Everytime the first world wonder has been researched the game's main view becomes all black and the world wonder's video is shown in a little window in the middle of the screen. Once the video is over, the game's main screen does not reappear. It stays all black.
I then saved the game. Then I restarted and tried loading the save game, but the game ist stuck in the loading screen eternally.

Reproduction

100% reproducible. I start a new game, research a world wonder, and all goes black again.
Or I try loading a game saved after the world wonder - everything is black.

Start by reproducing the issue with Civilization IV AppID 3900 using the listed Proton versions, then inspect steam-3900.log alongside the reported system information. Verify whether completing a world wonder causes the main view to remain black and whether saves made afterward load successfully; done means both views and saved games recover normally.