crash on line staging

[extrawurst]

panic: PanicInfo { payload: Any, message: Some(index out of bounds: the len is 2 but the index is 2), location: Location { file: "asyncgit/src/sync/staging/mod.rs", line: 44, col: 25 } }
trace:
   0: backtrace::capture::Backtrace::new
   1: gitui::set_panic_handlers::{{closure}}
   2: std::panicking::rust_panic_with_hook
   3: std::panicking::begin_panic_handler::{{closure}}
   4: std::sys_common::backtrace::__rust_end_short_backtrace
   5: _rust_begin_unwind
   6: core::panicking::panic_fmt
   7: core::panicking::panic_bounds_check
   8: asyncgit::sync::staging::NewFromOldContent::add_old_line
   9: asyncgit::sync::staging::apply_selection
  10: <gitui::components::diff::DiffComponent as gitui::components::Component>::event
  11: gitui::components::event_pump
  12: <gitui::tabs::status::Status as gitui::components::Component>::event
  13: gitui::components::event_pump
  14: gitui::main
  15: std::sys_common::backtrace::__rust_begin_short_backtrace
  16: _main