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* Fixed bug: Ticker message about a car accident is removed too quickly.
* Fixed bug: Old pre-set buses in scenarios have wrong capacity.
* Fixed bug: Achievement "Four corners of the earth" can be unlocked only in sandbox mode.
* Improvement: Some optimizations when saving game.
* Improvement: Number of private cars depends on the difficulty setting
* (Slider for the custom difficulty).
* Improvement: Slower economy changes.
* Improvement: Shortcut key for underground view (default: U).
* Improvement: Jammed cars are removed faster.
* Fixed bug: Stops show wrong passenger count after a line is deleted.
