Possibly at [this](https://github.com/neovim/neovim/commit/23fe6dba138859c1c22850b9ce76219141f546a0) commit, the signature of the handler has changed and is breaking this plugin. [This](https://github.com/ojroques/nvim-lspfuzzy/blob/6f2cfbd0dffdbf0c74db5a3f91e2e65c27af545f/lua/lspfuzzy.lua#L90) code might be indirectly affected by the signature change.