So, I built the master branch of wxWidgets (but I had to manually download src/expat, src/jpeg, src/png, src/tiff and src/zlib - no idea why). I have got a billion of *.d and *.o files after one hour of building.
Then I built the samples/stc and I have got stctest.exe. If I try run it I have got system error in this sense: "Code not possible to run because wxmsw314u_gcc_cb.dll not found. Bla bla."
I have only "codeblocks-20.03\wxmsw313u_gcc_cb.dll" file.
Should I build exactly the tag wx3.1.3 as you suggested as a second possibility? Or could be the reason in the manually downloaded directories mentioned above?
Note: For the building I have used the command
mingw32-make -f makefile.gcc USE_XRC=1 SHARED=1 MONOLITHIC=1 BUILD=release UNICODE=1 USE_OPENGL=1 VENDOR=cb CXXFLAGS="-fno-keep-inline-dllexport" >log.txt 2>&1
from your link.