Comment 3 for bug 584964

While there may be a readability issue, using a comma is grammatically incorrect. GNOME is a restrictive appositive in this sentence. There are multiple 'more popular graphical desktop environments', so specifying GNOME by name further restricts the scope. If the phrase had been 'the most popular graphical desktop environment', then you could use a comma because specifying the name doesn't further restrict the scope.

As to the readability: The sentence could be rephrased:

"Ubuntu is just one of many different Linux distributions and uses GNOME, one of the more popular graphical desktop environments."

(In this case, the comma is necessary because the phrase 'one of the more popular graphical desktop environments' is nonrestrictive—that is, it doesn't further limit the scope (as GNOME is as specific as we can get); it just provides ancillary information.)

If you prefer the rewritten sentence or have a different suggestion for rewriting the sentence, reopen this bug and let me know.

Thanks!