frosch opened the ticket and wrote:

There are some functions in src/newgrf_*.cpp which use _current_company if there is no specific objects whose owner can be used. E.g. when querying stuff for the purchase list.
These functions are called from the GUI, the AIs and also from the commands, so using _local_company is wrong as well.

_current_company is set to _local_company on various user interactions, e.g. when clicking with the mouse or hitting keys. In other cases (e.g. when renaming a town) it is set to spectator. So if e.g. purchase lists are drawn after such a command but before the next mouse click the queried information is wrong.

Maybe _current_company should just get assigned to _local_company during any GUI stuff.

Reported version: trunk
Operating system: All

This issue was imported from FlySpray: https://bugs.openttd.org/task/3804