Can we please forget about the fallacy of "many votes" == "good"? Most of the most upvoted things on the entire network, you ask them nowadays and you will get a rain of downvotes/closevotes.
The fact that a question was/is "popular" at some moment of the time, and gathered lots of upvotes, despite being bad questions by today's standards, needs to be removed of the site. That is one of those cases where drive-by bad voters (judging for the quality of the votes) or that was asked when is was considered a good question.
Now, moving on. The question is intrinsically bad for the Q&A SE model. Is unclear, too broad and primary opinion based.
Is unclear since it's vague. Is akin to "ok, I have a program, can I upgrade, because I haven't tested anything?" (and please, that's what the question says). It doesn't show any relevant piece of code that would potentially break during the upgrade, nor any detail that would help trying to figure out if his software would even break. This is even more supported by a comment asking more information which OP decided to ignore.
Too broad, since any and every answer would be equally valid. You can say, "if you don't use these functions [puts list of functions] you can upgrade without problems" as you can say any other thing. There isn't a wrong answer.
Won't a recent Ubuntu version affect my software in any way ?
You can gather opinions too! The above question can be answer with "I did with my program, you are going to be fine" or "my program broke terribly, and had to rewrote it". That kind of experience/expertise is ultimately unuseful. If I don't have a program exactly the same as the one providing the answer, is not going to help me. But, hey, someone had the same experience, hence upvoted the answer, and there goes quality.
OP haven't made any effort to fix his question at all after it was closed. In fact, each edition just made it worse while it was opened and I highly doubt he would fix it now that he already got the answers he wanted. He got suspended, so I doubt any effort right now would help either, so I just voted delete the question.
Solutions for the good answers. (?)
Again I agree with the closure but ideally I'd have left this question for reference.
If you think that your answer is good but the question doesn't make live up to the goodness of your answer, just re-ask the correct question, with a clear statement, and post again your answer. I've done that too! I didn't get as many upvotes, but hey, I never said I do it for the
money imaginary internet points. So, if you were me, and you aren't doing it for the imaginary internet points, I would just ask another question where your answer would be found easily (if you want pointers about how can you ask your question just ask in comments).