LucidityofPower posted Q1 (below) which was closed as a duplicate of Q2.
Q1. Is this sentence grammatical: “all there is, are idiolects?” [duplicate]
Q2 is an example of the double copula, but as my answer to Q1 argues, apart from an extraneous comma, the quoted phrase in Q1 doesn't contain a double copula. (Note: there is also a possible issue with singular / plural agreement, but that's not addressed by Q2 either.)
I've proposed reopening the question, but so far there are only 3 votes to reopen. Is Q1 really a duplicate of Q2? If not, could I please request that more people vote to reopen the question?
A separate issue is whether the question is a low-quality question. I don't think it is, though I also invite replies about this. The is/are collocation is quite interesting, as is the issue about whether noun phrase admits both singular and plural agreement depending on context.