(gdb) break file-editor.cc:945 Breakpoint 1 at 0x7f6dbfcb1157: file libgui/src/m-editor/file-editor.cc, line 945. (gdb) break file-editor.cc:345 Breakpoint 2 at 0x7f6dbfcaf135: file libgui/src/m-editor/file-editor.cc, line 345. (gdb) break file-editor.cc:350 Breakpoint 3 at 0x7f6dbfcaf15e: file libgui/src/m-editor/file-editor.cc, line 350. (gdb) cont Continuing. --> gui is running. now close the 2nd tab in the gui with the mouse. Thread 1 "lt-octave-gui" hit Breakpoint 2, octave::file_editor::activate (this=0x1f64640) at libgui/src/m-editor/file-editor.cc:345 345 emit fetab_set_focus (fileEditorTab); (gdb) cont Continuing. --> i don't know from where this hit is comming? Thread 1 "lt-octave-gui" hit Breakpoint 1, octave::file_editor::handle_tab_remove_request (this=0x1f64640) at libgui/src/m-editor/file-editor.cc:945 945 activate (); // focus stays in editor when tab is closed (gdb) cont Continuing. --> in file_editor::handle_tab_remove_request the tab is actually deleted in a for loop. it follows a file_editor::activate call following emit of the fetab_set_focus (m_tab_widget->currentWidget ()) signal. Thread 1 "lt-octave-gui" hit Breakpoint 2, octave::file_editor::activate (this=0x1f64640) at libgui/src/m-editor/file-editor.cc:345 345 emit fetab_set_focus (fileEditorTab); (gdb) cont Continuing. problem: here a hit of file-editor.cc:350 should occur but it does not --> breakpoint file-editor.cc:350 setFocus () #### opening of the second file: (gdb) break file-editor.cc:1533 Breakpoint 1 at 0x7f83a72d8e99: file libgui/src/m-editor/file-editor.cc, line 1533. (gdb) break file-editor.cc:1542 Breakpoint 2 at 0x7f83a72d8f37: file libgui/src/m-editor/file-editor.cc, line 1542. (gdb) cont Continuing. Thread 1 "lt-octave-gui" hit Breakpoint 1, octave::file_editor::request_open_file (this=0x15bb470, openFileName=..., encoding=..., line=-1, debug_pointer=false, breakpoint_marker=false, insert=true, cond=..., index=-1) at libgui/src/m-editor/file-editor.cc:1533 1533 fileEditorTab = make_file_editor_tab (); (gdb) cont Continuing. Thread 1 "lt-octave-gui" hit Breakpoint 2, octave::file_editor::request_open_file (this=0x15bb470, openFileName=..., encoding=..., line=-1, debug_pointer=false, breakpoint_marker=false, insert=true, cond=..., index=-1) at libgui/src/m-editor/file-editor.cc:1542 1542 add_file_editor_tab (fileEditorTab, "", index); (gdb) cont Continuing.