frosch opened the ticket and wrote:

Applies to both 0.7.2 and trunk.

By editing openttd.cfg you can create presets which contain the same newgrf resp. newgrfs with same grfid multiple times.

When starting a new game with such presets the list is filtered and duplicate files and duplicate grfids are removed. However, when applying grfs ingame the list is not filtered and all grfs are activated.

When one instance of the grf causes the grfid to be deactivated (in the test scenario due to exceeding maximum number of grfs) OTTD crashes when loading subsequent newgrfs. Either by assert "src/newgrf.cpp:6222: void LoadNewGRF(uint, uint): Assertion 'GetFileByGRFID(c->grfid) == _cur_grffile' failed." or if disabled by usererror
"Error: File '<some subsequent newgrf' lost in cache."

Reported version: 0.7.2
Operating system: All

This issue was imported from FlySpray: https://bugs.openttd.org/task/3197