Game takes a lot of time to start - 14 minutes

[as400l]

Describe the bug

I installed Richard Burns Rally (Rallysimfans). Game works but it needs 14 minutes to start. During this startup time I see 6 or 7 threads of xdg-document-portal taking good chunk of CPU time.
It looks like storage access is very slow. Bottles is not throwing any errors.

I am not sure whether it's a Bottles problem. If not please do close this issue.

To Reproduce

1. Install Rallysimfans RBR.
2. Pick whichever runner.
3. Try to start a game.

Package

Flatpak from Flathub

Distribution

Fedora 40

Debugging Information

Official Package: true
Version: '51.11'
DE/WM: plasma
Display:
    X.org: true
    X.org (port): :0
    Wayland: true
Graphics:
    vendors:
        intel:
            vendor: intel
            envs:
                DRI_PRIME: '1'
            icd: /usr/lib/x86_64-linux-gnu/GL/vulkan/icd.d/intel_hasvk_icd.x86_64.json:/usr/lib/x86_64-linux-gnu/GL/vulkan/icd.d/intel_icd.x86_64.json:/usr/lib/i386-linux-gnu/GL/vulkan/icd.d/intel_hasvk_icd.i686.json:/usr/lib/i386-linux-gnu/GL/vulkan/icd.d/intel_icd.i686.json
    prime:
        integrated: null
        discrete: null
Kernel:
    Type: Linux
    Version: 6.8.7-300.fc40.x86_64
Disk:
    Total: 16583131136
    Free: 16582963200
RAM:
    MemTotal: 30.9GiB
    MemAvailable: 23.4GiB
Bottles_envs: null

Troubleshooting Logs

No response

Additional context

No response

[as400l]

@mirkobrombin - just to let you know, because I see my issue was transferred here.
In the meantime I have installed Bottles from the Fedora repository and game starts up waaaay faster.

I'm not saying it is Bottles bug but definitely some underlying technology is slow. Either xdg-document-portal or a fuse mount.