S25 crashes hard

[Andreas Rayo Kniep]

In the latest versions, the game sometimes crashes hard without warning or saving the state (savegame).
Back in the days with the asynchronous problem, the game created a savegame, but this bug is worse.
This is the only error message I could save:
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Failed loading glXSwapIntervalSGI: dlsym(0x7fff63438960, _glXSwapIntervalSGI): symbol not found
Failed loading glXSwapIntervalSGI: dlsym(0x7fff63438960, _glXSwapIntervalSGI): symbol not found
libc++abi.dylib: Pure virtual function called!
/Applications/games/Siedler25_s25_RttR_ReturnToTheRoots/s25client.app/Contents/MacOS/rttr.command: line 61: 2497 Abort trap: 6 ./bin/s25client
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As a side note:
The asynchonous problem only very rarely occurs nowadays.
But instead, sometimes players just get kicked out of the game, without warning or automatic saving. It just says in the top left corner: "Spiele XYZ hat das Spiel verlassen"... That's all.

[Spike (fvv1)]

If this bug still appears in the latest nightly builds, re-report it on github.