The old stable release that is currently availablein portage, 1.4.589.29_p1, suffers from https://bugs.chromium.org/p/chromium/issues/detail?id=664177, which causes many major websites to fail certificate validation. There's a newer stable release, 1.4.589.41_p1, where certificate validation on affected sites works correctly.
In the mean time, a stable 1.5 release has been made, so we might as well bump to that directly…