Hello…
You know the “buy me a coffee” button that appears in the developers’ profile and at the bottom of the games:
If what you actually want is to display your socials, maybe it would be better to provide an option for doing so instead of hacking the donation button for that 
I’d rather put socials before the donate button. I agree that custom links, text and icons are very important, but it’d be cool to have the correct username and icon displayed automatically for supported platforms, quick mockup:
This looks great, they should really add this, but I think that customizing a button seems more important, especially for people who have a website, and perhaps if each game had its own button as a download button from other sites, it would be more professional
I like it. For me gd.games should have more customization also in the personal pages of the authors, not just under the games. A cover image, links for your social networks, donations, the possibility of asking questions to the author, a kind of “ask me something”, follow this author, receive notifications from the author when he publishes something, a personal bulletin board where you can write various updates (like Twitter I thought) and which are possible to comment, the comments under the game, the reviews (to decide whether you want to enable them or not, a bit like Early Access games on PlayStore and Steam), how many people have shared game link. Beyond this it would be great to make it the new Itch.io, with the possibility of buying games, dlc and so on (Even if at the moment it is not what it needs)
Little feedback:
https://twitter.com/arthuro555 → @arthuro555.