[[!comment format=mdwn
 username="https://me.yahoo.com/zoredache#d4929"
 nickname="Zoredache"
 subject="comment 2"
 date="2016-06-20T19:38:40Z"
 content="""
> If there are any error or warning messages, they'd be in your web server's error log

No obvious errors in the log.  When I attempt to attach something, all I see is some stuff from git, that I seem to see with every modification.

    [Mon Jun 20 12:32:29.322642 2016] [cgi:error] [pid 35431] [client 10.2.4.243:51566] AH01215: To /srv/www/notes.example.org/wiki/wiki.git, referer: https://notes.example.org/wikicgi/ikiwiki.cgi
    [Mon Jun 20 12:32:29.322688 2016] [cgi:error] [pid 35431] [client 10.2.4.243:51566] AH01215:    3afefec..a6ad76c  master -> master, referer: https://notes.example.org/wikicgi/ikiwiki.cgi

> What version of ikiwiki are you using?, Which OS distribution?

I am seeing the same results on a couple systems of various configs.  The newest version is running on a Debian Jessie system with the backports ikiwiki.

    # apt-cache policy ikiwiki
    ikiwiki:
      Installed: 3.20160509~bpo8+1
      Candidate: 3.20160509~bpo8+1
      Package pin: 3.20160509~bpo8+1
      Version table:
     *** 3.20160509~bpo8+1 600
            100 http://httpredir.debian.org/debian/ jessie-backports/main amd64 Packages
            100 /var/lib/dpkg/status

> What version of CGI.pm?

    # head -2 /usr/share/perl/5.20.2/CGI.pm 
    package CGI;
    require 5.008001;
    # dpkg -S /usr/share/perl/5.20.2/CGI.pm
    perl-modules: /usr/share/perl/5.20.2/CGI.pm
    # apt-cache policy perl-modules
    perl-modules:
      Installed: 5.20.2-3+deb8u5
      Candidate: 5.20.2-3+deb8u5
      Version table:
     *** 5.20.2-3+deb8u5 0
            500 http://httpredir.debian.org/debian/ jessie/main amd64 Packages
            100 /var/lib/dpkg/status

"""]]