- Your initial post is plagiarism, since you copy/pasted an article without adding a reference.
- After being pointed out, you added the reference to the article. That technically lets you off the hook from there on.
- Nevertheless, as I mentioned in that same thread, unless it’s something pressing (i.e. virus alert or this evenings lottery winning numbers), simply performing a copy/paste and adding a source is pretty lazy, and may even be considered a low value post. Really, simply invest 10-15 minutes to summarize it, or to add a versed opinion (in favour, against, whatever). That could bring something to the table that is worth discussing.
In short, no, with the added reference it is not plagiarism technically, although I personally see no added value. Somebody could have reported you on your initial OP, since it lacked the source which was added later. If a mod would have processed the report before you added a link, then he would have nuked your account …
Edit: I assume you are not banned, since this OP on Meta is not a Ban Appeal.