Should work fine, but do you have adblock installed (could be the /dev/null issue, see Adblock support thread - #3415 by dave14305 (and solution in Adblock support thread - #3426 by dave14305). Check that and report back.
(Note that your 2GB partition will be resized to 104MB and your config will be lost on upgrade. See https://openwrt.org/docs/guide-user/installation/sysupgrade.owut#expanding_root_file_system for details.)