_add_file->SetToolTip (_("Add video, image, sound or subtitle files to the film."));
b->Add (_add_file, 0, wxEXPAND | wxALL, DCPOMATIC_BUTTON_STACK_GAP);
_add_file->SetToolTip (_("Add video, image, sound or subtitle files to the film."));
b->Add (_add_file, 0, wxEXPAND | wxALL, DCPOMATIC_BUTTON_STACK_GAP);