lyx 2.4.0dev crashes

[Wolfgang Engelmann]

I start lyx

Version 2.4.0dev (not released yet)
Built from git commit hash 53ed3dc0
Qt Version (run-time): 5.15.2 on platform xcb
Qt Version (compile-time): 5.15.2
Python detected: python3 -tt

on a terminal

$ lyx

but it crashes with this output on the terminal:

qt.qpa.xcb: QXcbConnection: XCB error: 5 (BadAtom), sequence: 598, 
resource id: 0, major code: 20 (GetProperty), minor code: 0
/usr/include/c++/10/bits/stl_stack.h:274: void std::stack<_Tp, 
_Sequence>::pop() [with _Tp = int; _Sequence = std::__debug::deque<int, 
std::allocator<int> >]: Assertion '__builtin_expect(!this->empty(), 
true)' failed.
Abgebrochen

what should I do?

Wolfgang