Chromium

:: This Chromium package no longer supports custom flags passed via the
   /etc/chromium/default file (or any other files under /etc/chromium/).

   The new /usr/bin/chromium launcher script will automatically detect
   Pepper Flash (if installed) and pass the correct flags to Chromium.

   If you need to pass extra command-line arguments to Chromium, you
   can put them in a "chromium-flags.conf" file under $HOME/.config/
   (or $XDG_CONFIG_HOME). Arguments are split on whitespace and shell
   quoting rules apply but no further parsing is performed.