Fix inconsistent behaviour and crashes with LaTeX input cells in spli…

…t views.

frontend/gtkmm/NotebookWindow.cc

@@ -1212,7 +1212,7 @@ void NotebookWindow::add_cell(const DTree& tr, DTree::iterator it, bool visible)
 #ifdef DEBUG
 			std::cerr << "found a visualcell for cell " << &(*it) << " in canvas " << i << std::endl;
 #endif
-			if(i==0 && it->cell_type==DataCell::CellType::python) {
+			if(i==0 && (it->cell_type==DataCell::CellType::python || it->cell_type==DataCell::CellType::latex)) {
 				global_buffer = canvasses[i]->visualcells[&(*it)].inbox->buffer;
 				}
 			continue;
@@ -1699,8 +1699,10 @@ bool NotebookWindow::cell_toggle_visibility(DTree::iterator it, int )
 	if(parent->cell_type==DataCell::CellType::latex) {
 		// FIXME: we are not allowed to do this directly, all should go through
 		// actions.
+		std::cerr << "toggling visibility" << std::endl;
 		parent->hidden = !parent->hidden;
 		for(unsigned int i=0; i<canvasses.size(); ++i) {
+			std::cerr << "canvas " << i << std::endl;			
 			auto vis = canvasses[i]->visualcells.find(&(*parent));
 			if(vis==canvasses[i]->visualcells.end()) {
 				throw std::logic_error("Cannot find visual cell.");