that contribution of yours is greatly appreciated, no doubt to it.
with that being said, this is a community wiki. to say it bluntly, if you're doing something just for the credit, you're doing it with the wrong heart. misplaced priorities.
in any case, i've replaced your original screenshot with a better looking one, so if you want to be upset, do it to me.
The only "claim" going on here is you claiming that F-sharp had any amount of malice when they uploaded the PNG. They didn't "steal credit" from you; even by giving you benefit of the doubt, F-sharp couldn't have done it intentionally.
To answer your question, though, I wouldn't care. There are always other ways to contribute to the community.
Besides, none of this is our IP, so why be this salty over it?
Greetings, reader. My name is Jack. This is a personal but public log- I'm mostly intending it for my own use, but you are always free to reference it.
This log details anomalies in the interface of Undertale. These anomalies are generally related to how the narrator, player, Frisk, and monsters interact within the game in the various different menus: Battles, dating, and overworld choices (though dating might be seen as a subcategory of battles).