Compatibility Report

• Name of the game with compatibility issues: Conquest Frontier Wars
• Steam AppID of the game: 578670

System Information

• GPU: AMD RX 6500 XT
• Video driver version: Mesa 26.0.3
• Kernel version: 6.19.9
• Link to full system information report as Gist: https://gist.github.com/apemax/5b227982377ef37dc641b1d62646adc4
• Proton version: 10.0-4

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.

Proton log:

steam-578670.log

Symptoms

The third intro video does not play, Only a test card image is displayed. I believe this is related to the below error message found in the log:

winegstreamer error: decodebin12: Your GStreamer installation is missing a plug-in.
winegstreamer error: decodebin12: ../src-gst_base/gst/playback/gstdecodebin2.c(4704): gst_decode_bin_expose (): /GstBin:bin12/GstDecodeBin:decodebin12:
no suitable plugins found:
Missing decoder: MPEG-1 System Stream (video/mpeg, systemstream=(boolean)true, mpegversion=(int)1)

I have tried this with Proton 10.0-4, 9.0-4, Experimental, Hotfix.

Reproduction

1. Install Conquest: Frontier Wars.
2. Select Proton 10.0-4 as the proton version.
3. Start the game and notice when the third intro video should play you only get a test card image instead.