Because configure is called with these options in order: --enable-video --disable-video (because of --minimal)
Created attachment 76321 [details] proposed patch
Not really GTK specific.
Comment on attachment 76321 [details] proposed patch It doesn't work, because there isn't --enable-video option in build-webkit script. You can use --video to enable and --no-video to disable video support. This code sets the default value or 0 if you passed --minimal option : ... # Initialize values from defaults foreach (@features) { ${$_->{value}} = ($_->{default} && !$minimal) || 0; } ... But the script processes the command line arguments later: ... # Build usage text and options list from features foreach (@features) { my $opt = sprintf("%-35s", " --[no-]$_->{option}"); $usage .= "$opt $_->{desc} (default: $_->{default})\n"; $options{"$_->{option}!"} = $_->{value}; } ... So "build-webkit --minimal --video" will work for you and it isn't a bug.