Hello thank you for that mod. I was waiting for something like that - with high mining productivity stacking is problematic.
Space Exploration specific ores cannot be stacked/unstacked (but can be mined without problem).

I'll look into it (maker of the SE deadlock bridge).
Edit: Be adviced, you're stakcing items without adding any way to unlock the unstacking recipes. This means that any ore that's not already being stacked by other mods ends up being unusable.

Upload a fix on my end.

Is it at all possible for you to add the stacked ores in final fixes? Would probably have less issues with other mods adding stacked ores a bit later.

Thanks for the report and thanks Mernom.

I thought that the function deadlock.add_stack() automatically creates a stack and an un-stack recipe AND adds a way to unlock them to the deadlock-stacking-1 technology. Seems like I have to specify a target_tech in the function for that.

Looking at other deadlock support mods, it makes a lot of sense to add them in final fixes, sorry about that. I will do that.

The reason why I was adding them in data updates in the first place was that when I create the stacked ores (entity), I checked if stacked versions of the mining results exist and if not, create them, to make sure that the mining results of the stacked ore (entity) exists.

Moving the creation of the stacked ores (items) to the end of data final fixes could (probably?) cause other problems, so I will have to split it into 2 parts.

Is there a smarter way than creating the stacked ores (entity) with normal (unstacked) mining results and then checking at the end of data final fixes (enforce that with optional dependencies) if a stacked ore version (item) of the mining results exist and if not, create them?

EDIT:
I made the changes like I described above but I don't have the time to do some testing so I will wait until tomorrow with uploading the new version.

If the game crashes when you have the mining result be a non-existent item, you can make a placeholder item and add the ore that were not properly added to a global list, then during data final fixes, check again if the stacked ores exist, if not make your own variant, and replace the placeholder items with the proper stacked items?