Only one window can be opened

After updating to v2.3.5, only one window can be opened, is it a bug? My system is Ubuntu 18.04 in WLS.

You should be able to start cadabra2-gtk multiple times; that certainly works on Ubuntu 18.04 on bare metal. Using File / New is not intended to open an extra window (essentially, every instance of cadabra2-gtk has one kernel, and if you want more than one kernel you just start a new instance).

Or are you talking about the Jupyter kernel?

With a few rare exceptions, providing binaries/installers is all on my shoulders, and I simply do not have the time anymore to battle with Windows. Despite many people asking for a Windows version, no-one has stepped up to help with building it.

Got it. Maybe I should also report this bug to WLS developer. I will try other ways. Thanks for your explanation.

When I install from source, I get the following warning

[ 22%] Building CXX object core/CMakeFiles/cadabra2.dir/Adjform.cc.o
if (counts.size() <= perm[i])
if (elem > i)
~~~~~^~~
for (size_t j = 0; j < perm[i]; ++j) {
else if (data[i] > i) {

No, these are warnings which are related to the meld algorithm only.