private String fetchBlacklist() {
        String regexp = "";
        try {
            // TODO: replace with Data.settings.server after checking behaviour when there is no local blacklist on wiki
            String prefixes = new Wiki("commons.wikimedia.org").getPageText("MediaWiki:Filename-prefix-blacklist");
            String[] prefixesList = prefixes.replaceAll("(?m)#.*", "").trim().split("\\s+");
            for (String prefix : prefixesList) {
                regexp += prefix + "|";
            }
            if(regexp.endsWith("|")) {
                regexp = regexp.substring(0, regexp.length() - 1);
            } 
            regexp = "^(" + regexp + ").*";
        } catch (IOException ex) {
        }
        return regexp;
    }