Description of problem:
Running amule on the commandline results in a crash.

Version-Release number of selected component (if applicable):
amule-2.4.0-0.git20200518.2.mga8
lib64wx_baseu3.1_4-3.1.4-1.mga8
I did recompile amule to see if that gave any different result. The backtrace below was taken after that rebuild.

This is the backtrace in gdb:

$ gdb amule
GNU gdb (GDB) 9.2-1.mga8 (Mageia release 8)
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Reading symbols from amule...
Reading symbols from /usr/lib/debug/usr/bin/amule-2.4.0-0.git20200518.2.mga8.x86_64.debug...
(gdb) run
Starting program: /usr/bin/amule 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7ffff29be700 (LWP 36779)]
[New Thread 0x7ffff21bd700 (LWP 36780)]
[Detaching after vfork from child process 36781]
 2020-09-05 22:05:45: Initialising aMule 2.4.0 (SVN 20200518) compiled with wxGTK2 v3.1.4 and Boost 1.73
 2020-09-05 22:05:45: Checking if there is an instance already running...
 2020-09-05 22:05:45: No other instances are running.
[Detaching after vfork from child process 36783]
[Detaching after vfork from child process 36785]
[Detaching after vfork from child process 36787]
[Detaching after vfork from child process 36789]
[Detaching after vfork from child process 36794]
[Detaching after vfork from child process 36799]
[Detaching after vfork from child process 36804]
 2020-09-05 22:05:46: ListenSocket: Ok.

Thread 1 "amule" received signal SIGTRAP, Trace/breakpoint trap.
0x00007ffff6fce1b9 in wxDefaultAssertHandler(wxString const&, int, wxString const&, wxString const&, wxString const&) ()
   from /lib64/libwx_baseu-3.1.so.4
(gdb) bt
#0  0x00007ffff6fce1b9 in wxDefaultAssertHandler(wxString const&, int, wxString const&, wxString const&, wxString const&)
    () at /lib64/libwx_baseu-3.1.so.4
#1  0x00007ffff6fcb133 in wxOnAssert(char const*, int, char const*, char const*, char const*) ()
    at /lib64/libwx_baseu-3.1.so.4
#2  0x000000000067f45c in get_backtrace(unsigned int) (n=n@entry=2) at MuleDebug.cpp:388
#3  0x00000000004b4c4f in CamuleApp::OnAssertFailure(wchar_t const*, int, wchar_t const*, wchar_t const*, wchar_t const*)
    (this=0xab7030, file=0x338eba0 L"./src/common/sizer.cpp", line=2112, func=0x337c7c0 L"DoInsert", cond=0x3302730 L"!(flags & wxALIGN_CENTRE_VERTICAL)", msg=0x3375a70 L"Vertical alignment flags are ignored in vertical sizers")
    at amule.cpp:1087
#4  0x00007ffff6fce107 in wxDefaultAssertHandler(wxString const&, int, wxString const&, wxString const&, wxString const&)
    () at /lib64/libwx_baseu-3.1.so.4
#5  0x00007ffff6fcbf4a in wxOnAssert(char const*, int, char const*, char const*, wchar_t const*) ()
    at /lib64/libwx_baseu-3.1.so.4
#6  0x00007ffff7706e5d in wxBoxSizer::DoInsert(unsigned long, wxSizerItem*) () at /lib64/libwx_gtk3u_core-3.1.so.4
#7  0x00000000007da0fe in muleDlg(wxWindow*, bool, bool)
    (parent=parent@entry=0x29416b0, call_fit=call_fit@entry=false, set_sizer=set_sizer@entry=true) at muuli_wdr.cpp:69
#8  0x00000000005806bc in CamuleDlg::CamuleDlg(wxWindow*, wxString const&, wxPoint, wxSize)
    (this=<optimized out>, pParent=<optimized out>, title=..., where=..., dlg_size=...) at amuleDlg.cpp:232
#9  0x00000000005731b4 in CamuleGuiBase::InitGui(bool, wxString&)
    (this=0xab76c8, geometry_enabled=false, geom_string=...) at /usr/include/wx-3.1/wx/gdicmn.h:281
#10 0x00000000005735a4 in CamuleGuiApp::InitGui(bool, wxString&)
    (this=0xab7030, geometry_enable=<optimized out>, geometry_string=...) at amule-gui.cpp:256
#11 0x00000000004b48e9 in CamuleApp::OnInit() (this=this@entry=0xab7030) at /usr/include/wx-3.1/wx/string.h:3575
#12 0x0000000000573637 in CamuleGuiApp::OnInit() (this=0xab7030) at amule-gui.cpp:288
#13 0x00007ffff704270a in wxEntry(int&, wchar_t**) () at /lib64/libwx_baseu-3.1.so.4
#14 0x0000000000487362 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at amule-gui.cpp:95
(gdb)