i need help!
i tried unfunny science and the mod changed all belt, splitter and underground entities in all of my blueprints in my personal library.
so now i can't use my blueprints or alter them in anymore

All the entity names were changed so he could add an additional tier. You might try putting down a ghost then using the upgrade planner to change the entities. That's a longshot because I don't think it will place the ghosts at all.

It is possible to add additional tiers of belt without changing the internal names of existing ones, which would also increase compatibility with other mods.

I posted some Screenshots here in the factorio-subreddit before i found out that this mod is the culprid.
https://www.reddit.com/r/factorio/comments/14hwsto/help_some_mod_broke_my_complete_blueprint_library/

my problem is, that all of my blueprints containing belts, splitter and undergrounds have been replaced with the unfunny-modded version. If i try to use the blueprints without the unfunny mod, all entities are displayed as ein "?" symbol and the blueprints themself are locked.

For partial recovery of blueprints

revert back to unfunny science v. 0.1.0
make an upgrade planner
- belt 1 -> Transport belt
- splitter 1 -> Splitter
- underground belt 1 -> underground belt

same for belt(s) 2 and 3 , you can also put in here
Burner asembling machine 1 - > Assembling machine 1

put this upgrade planer to blueprints library
revert back to v. 0.1.7.
start new game a sandbox for instance.
put that upgrade planer to inventory.

check the blueprints and use upgrade planer to revert back to original transport belts.

This is partial solution as u dont have access to all conversion of entities. Some other required mods may not work together with unfunny science.
I for myself need to check 50-100 blueprints. But for larger librarys could be needed some other method.

how did you manage to get the old v.0.1.0 running?
i'm getting LUA-errors here (with only this mod here enabled)

I have removed all the mods. Except for the Un_science,its post process and maybe FNEI. And it was new Sandbox game.
Maybe some more clarification
-Start New game under v. 0.1.0. Make upgrade planer
-Start New game under v. 0.1.7. Check and repair blueprints

Loading map from v.0.1.0 under v.0.1.7 will not work i noticed that too.

And additional info to this case that i gathered on Internet.
This issue happens to those who update base mod game to higher version. So it is for those of us who play with Factorio [1.1.x].
So when we updated from base 1.1.84 to base 1.1.85 for instance our blueprints may have been changed with the upgrade.

Those who play on stable base 1.1.80 may not have changed theirs blueprints ... yet. But when next stable version goes live . some more peoples can wonder about theirs changed blueprints.

But unfunnyjoke27 has also some 50% faults in this. Since he disabled vanila entities and replaced them with his own.

did not know it would do this. fix should be posted in ~1-2 hrs

fix live, sorry about that.

Since you have put question mark after fixed.

I can confirm that the majority of blueprints are fixed and no longer require this mod. But I stilll have few instances with ??? belts. Dont know if it is due more mods conflicts, but I think nothing more can be done about this. So I can call it Sucesss.

Just an heads up message for those who are using Factorissimo or other linked belts. The link between these belts can be broken, so just redo your connections. Either from outside or inside of factory building.