Company shown story page again when buying out another company

If you buy out another company, you are eventually shown the story page again (the same way as from the start of the game), as if your company is being initialized again. This could be a significant issue if the company is actually initialized again, as you are basically "restarting" a company, although it did not seem like this is actually happening.

I assume this is happening because after a merge, the game keeps the old company id valid and referencing the old id references the new company. This is of course a generous assumption, and more testing needs to be done to see if this is the case.

The hardest part is figuring out how OpenTTD handles company ids when a company is merged. I assumed their company id would be invalid after a merge, but as I said that may not be the case.

Start by reproducing a company buyout in OpenTTD and observe whether the story page appears again. Investigate how OpenTTD handles company IDs after a merge, then verify whether the old ID triggers reinitialization or only causes the story page to be shown; done means the cause is confirmed and the repeated initialization behavior is resolved.

Written by the indexing model from the issue text.