Plugin Manager causes panic when opened from gnome application menu

[geoffritter]

1. Start with or without having an init.vim file and existing plugins
2. open neovim-gtk on Fedora 27 with Gnome 3.26.2 / Rust 1.23.0
3. click the application menu
4. click Plugins

RESULT Plugins manager briefly appears then the both the plugin manager and the main window close.

EXPECTED Plugins manager to open normally

thread 'main' panicked at 'already borrowed: BorrowMutError', src/libcore/result.rs:906:4 stack backtrace: 0: std::sys::imp::backtrace::tracing::imp::unwind_backtrace 1: std::sys_common::backtrace::_print 2: std::panicking::default_hook::{{closure}} 3: std::panicking::default_hook 4: std::panicking::rust_panic_with_hook 5: std::panicking::begin_panic 6: std::panicking::begin_panic_fmt 7: rust_begin_unwind 8: core::panicking::panic_fmt 9: core::result::unwrap_failed 10: <nvim_gtk::ui::UiMutex>::borrow_mut 11: nvim_gtk::ui::Ui::init::{{closure}} 12: gtk::auto::widget::window_state_event_trampoline 13: 14: g_closure_invoke 15: 16: g_signal_emit_valist 17: g_signal_emit 18: 19: gtk_main_do_event 20: 21: 22: g_main_context_dispatch 23: 24: g_main_loop_run 25: gtk_dialog_run 26: nvim_gtk::plug_manager::ui::Ui::show 27: nvim_gtk::ui::Ui::create_main_menu::{{closure}} 28: gio::auto::simple_action::activate_trampoline 29: g_closure_invoke 30: 31: g_signal_emit_valist 32: g_signal_emit 33: 34: 35: 36: 37: 38: g_main_context_dispatch 39: 40: g_main_context_iteration 41: g_application_run 42: nvim_gtk::main 43: rust_maybe_catch_panic 44: std::rt::lang_start 45: libc_start_main 46: _start Uncaught panic, exiting Aborted (core dumped)