"egrep" is deprecated, use "grep -E"

[gnw3]

From Debian bullseye/sid (unstable) "info grep" 👍

In addition, two variant programs ‘egrep’ and ‘fgrep’ are available.
‘egrep’ is the same as ‘grep -E’. ‘fgrep’ is the same as ‘grep -F’.
Direct invocation as either ‘egrep’ or ‘fgrep’ is deprecated, but is
provided to allow historical applications that rely on them to run
unmodified.

From README.md:

This package will only work in linux OS that have the egrep command.

Replacing egrep with grep -E would remove the above limitation. We can
expect future linux releases to remove egrep (as well as fgrep).