When building I saw an 1.6 GiB 3rdparty folder with chromium, gn and ninja Chromium also bundles a ton of other libraries
Chromium in QtWebEngine is heavily patched and certainly not unbundlable. Ebuilds have dependency on dev-util/ninja and in src_configure(): export NINJA_PATH=/usr/bin/ninja However it seems that value of NINJA_PATH is not used. Output of src_configure(): [[[ ... Checking for system ninja... yes ... Done running configuration tests. Configure summary: Qt WebEngine: ... Use System Ninja ....................... yes ... ]]] So NINJA_PATH can be dropped, and system ninja is still expected to be used.
(In reply to Alessandro Barbieri from comment #0) > When building I saw an 1.6 GiB 3rdparty folder with chromium, gn and ninja > Chromium also bundles a ton of other libraries We're aware, and unfortunately there's not much we can do about it. If you find some specific libraries that can be easily unbundled (without creating an unmaintainable mess), please let us know, but I'm afraid that unbundling the whole of chromium is simply not feasible.