This is (the beginning of) a script that will help build OnlyOffice in a reasonable way, without half the operating system its official build system bundles and builds.
Simply cd to the checkout directory and
run ./build.sh to build.
It results in a DesktopEditors binary in
desktop-apps/win-linux/build as well as various libraries
all over the place. Set LD_LIBRARY_PATH to make sure
DesktopEditors can find all the libraries it needs
(or simply use run.sh).
It compiles, and "works" if OnlyOffice is installed from binary packages and then the binaries are overwritten with the newly built binaries.
We currently don't have a way to build the remaining missing bits.
Another big problem is the CEF blob. While CEF is theoretically Open Source, it seems to be impossible to check out the source for older builds (OnlyOffice requires build 4280) because apparently some branches have been renamed and the build scripts hardcode the old names.