Fedora's missing Chromium updates

Either that, or have a common project among different distros to produce the source that gives you the options that distros want. That said, I think part of Gentoo's ability to build Chromium well is due to it being able to update system library packages to versions without matching ABIs by rebuilding other packages when necessary. (Also, possibly, the use of slots to let Chromium use a version of a system library that Chromium has been tested with and requires, but no other software in the distro has been tested with yet.)