Are you referring to this one: How to download and install java plugin for firefox 19.0
If so, I am then the evil man that marked that question as duplicate.
Is not a bad thing and you do not have to do anything else. It just means that there was an already existing and answered question similar to yours on the site. The question that was used as the original was How do I install Java?
Which answers your question (In several ways made I add thanks to users like Bruno Pereira, Lekensteyn and others).
So do not worry about it. This is one of several methods we do here to have a neat and clean site that users can use to find the questions quickly without getting into confusion when they see several similar questions (Eg: Like looking for an Nvidia problem and finding 10 similar questions). Is not something bad you did, you might have just tried to search for the question in the beginning but could not find one or at least one that solved your problem.
