Use git clone https://github.com/resloved/i3.git
Paste the following into /usr/share/xsessions/i3.desktop
[Desktop Entry]
Name=i3
Comment=improved dynamic tiling window manager
Exec=i3
TryExec=i3
Type=Application
X-LightDM-DesktopName=i3
DesktopNames=i3
Keywords=tiling;wm;windowmanager;window;manager;
Hello. Same error @Marculonis21 said.
autoreconf: 'configure.ac' or 'configure.in' is required
and i tried this: apt install build-essential libboost-all-dev cmake flex... but this not the solution