bug#35243: ungoogled-chromium build stops and freezes the system

[znavko]

My bug report is this https://github.com/Eloston/ungoogled-chromium/issues/730

During update with `guix pull && guix package -u` ungoogled-chromium build process stops on build derivation on 84% three times in a row.

$ guix describe
Generation 94 Apr 11 2019 21:13:38 (current)
guix a6de569
repository URL: https://git.savannah.gnu.org/git/guix.git
branch: master
commit: a6de569ea224a2f482c4d13c5f62240d1b1543a0

$ chromium --version
Chromium 73.0.3683.86

It shows this error message http://0x0.st/zNo0.jpg
"A script on this page may be busy, or it have stopped responding...
Script:chrome://global/content/bindings/popup.xml:276"