In /usr/bin/screen-ir line 14:
test -f ${HOME}/.screen-irrc && . ${HOME}/.screen-irrc
        ^-----^ SC2086: Double quote to prevent globbing and word splitting.
                                  ^------------------^ SC1090: Can't follow non-constant source. Use a directive to specify location.
                                  ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
test -f "${HOME}"/.screen-irrc && . "${HOME}"/.screen-irrc


In /usr/bin/screen-ir line 19:
    egrep '^ [0-9]' | \
    ^---^ SC2196: egrep is non-standard and deprecated. Use grep -E instead.


In /usr/bin/screen-ir line 21:
    iselect -a -t "Select screen session to reattach" $ISELECT_OPTIONS | \
                                                      ^--------------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    iselect -a -t "Select screen session to reattach" "$ISELECT_OPTIONS" | \

For more information:
  https://www.shellcheck.net/wiki/SC1090 -- Can't follow non-constant source....
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
  https://www.shellcheck.net/wiki/SC2196 -- egrep is non-standard and depreca...