Code review comment for lp://staging/~widelands-dev/widelands/new-tutorials

> > This fixed another crash.
>
> Did you check that everything still works? This has never crashed so far.
> Normally, the given panels should all exist.

Yes, I did check - at least I didn't notice any adverse effects.

> And why did you only write about sentries in tut01? The player can build other
> buildings, too (at least if he waits long enough for the lumberjack to cut
> down some trees).

Oops, I thought that the sentry was the only building in the allowed list. I thought it would be easier for the player if we are more specific here. Please feel free to change this back.