Vincent van Ravesteijn wrote:
> an easy fix is to revert some other fix of me, although it destroys what I 
> tried to fix.

working with the file for some time, then i tried to close next tab with unsaved
new file, after pushing discard changes i got new crash, don't know if related:

std::_Rb_tree<int, std::pair<int const, lyx::ParagraphMetrics>, std::_Select1st<std::pair<int const, lyx::ParagraphMetrics> >, std::less                                     
<int>, std::allocator<std::pair<int const, lyx::ParagraphMetrics> > >::_M_erase (this=0x887a948, __x=0x439)
    at /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_tree.h:1264
1264              _M_erase(_S_right(__x));
(gdb) bt
#0  std::_Rb_tree<int, std::pair<int const, lyx::ParagraphMetrics>, std::_Select1st<std::pair<int const, lyx::ParagraphMetrics> >, std::less<int>, std::allocator<std::pair<int const, lyx::ParagraphMetrics> > >::_M_erase (this=0x887a948, __x=0x439)
    at /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_tree.h:1264
#1  0x081dcb01 in std::_Rb_tree<int, std::pair<int const, lyx::ParagraphMetrics>, std::_Select1st<std::pair<int const, lyx::ParagraphMetrics> >, std::less<int>, std::allocator<std::pair<int const, lyx::ParagraphMetrics> > >::operator= (this=0x887a948, __x=@0x8c8a930)
    at /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_tree.h:692
#2  0x081cdbd4 in lyx::Text::dispatch (this=0x8bbcccc, cur=@0x8bf0828, cmd=@0xbfd87d70)
    at /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/include/g++-v4/bits/stl_map.h:227
#3  0x08240744 in lyx::Cursor::dispatch (this=0x8bf0828, cmd0=@0xbfd88864) at Cursor.cpp:316
#4  0x0815db2f in lyx::LyXFunc::dispatch (this=0x885f040, cmd=@0xbfd88864) at LyXFunc.cpp:1705
#5  0x08168c72 in lyx::LyXFunc::processKeySym (this=0x885f040, keysym=@0xbfd88938, state=lyx::NoModifier) at LyXFunc.cpp:388
#6  0x0845987b in lyx::frontend::GuiWorkArea::keyPressEvent (this=0x8bb1b70, ev=0xbfd88f14) at GuiWorkArea.cpp:850
#7  0xb77894e2 in QWidget::event () from /usr/lib/qt4/libQtGui.so.4
#8  0xb7abc393 in QFrame::event () from /usr/lib/qt4/libQtGui.so.4
#9  0xb7b51ddf in QAbstractScrollArea::event () from /usr/lib/qt4/libQtGui.so.4
#10 0x08459c0f in lyx::frontend::GuiWorkArea::event (this=0x8bb1b70, e=0xbfd88f14) at GuiWorkArea.cpp:626
#11 0xb7730f8f in QApplicationPrivate::notify_helper () from /usr/lib/qt4/libQtGui.so.4
#12 0xb7736423 in QApplication::notify () from /usr/lib/qt4/libQtGui.so.4
#13 0x084188fb in lyx::frontend::GuiApplication::notify (this=0x885eba8, receiver=0x8bb1b70, event=0xbfd88f14)
    at GuiApplication.cpp:1256
#14 0xb74f2397 in QCoreApplication::notifyInternal () from /usr/lib/qt4/libQtCore.so.4
#15 0xb778e3be in ?? () from /usr/lib/qt4/libQtGui.so.4
#16 0xb77bd3cb in ?? () from /usr/lib/qt4/libQtGui.so.4
#17 0xb77bf306 in ?? () from /usr/lib/qt4/libQtGui.so.4
#18 0xb779a8ce in QApplication::x11ProcessEvent () from /usr/lib/qt4/libQtGui.so.4
#19 0xb77c0663 in ?? () from /usr/lib/qt4/libQtGui.so.4
#20 0xb74f156d in QEventLoop::processEvents () from /usr/lib/qt4/libQtCore.so.4
#21 0xb74f170d in QEventLoop::exec () from /usr/lib/qt4/libQtCore.so.4
#22 0xb74f3886 in QCoreApplication::exec () from /usr/lib/qt4/libQtCore.so.4
#23 0xb77307b7 in QApplication::exec () from /usr/lib/qt4/libQtGui.so.4
#24 0x0814df16 in lyx::LyX::exec (this=0xbfd89770, argc=@0xbfd897a0, argv=0xbfd89824) at LyX.cpp:343
#25 0x08071c8a in main (argc=1, argv=0x8bbcccc) at main.cpp:46