That's much cleaner. My original confusion arose from not understanding that surface.get_chunks can return some chunks where is_chunk_generated is false.

Thanks, I'm glad there's a reasonable explanation. For newly created maps, using on_chunk_generated is a good solution. (I checked, and the event is generated even for the initial chunks.) When the mod is added to an existing map, the mod will not get chunk_generated notifications for existing chunk...

What I did I'm creating a mod which calls LuaSurface.set_tiles in the script.on_init event handler. Some of the tiles I've instructed it to set to concrete are not set to concrete, and vice versa. I've only noticed the glitches at the outermost initially generated chunks, i.e. slightly further out ...

TL;DR In the technology research screen, arrange the technology icons in columns instead of by rows. The highest level science pack required to research a technology determines which column that technology appears in. This suggestion is an enhancement of the reordering of technologies based on cost...

I've seen the same behavior, checked in 0.15.11. Here is the simplest reproduction I could come up with: 1. (a) In game A, create a new blueprint book, and add two blueprints to it. Call them BP1 and BP2. 1. (b) Add the blueprint book to the blueprint library. 1. (c) Save the game. 2. (a) In game B,...