Multiple themes don’t seem to be compatible with how resizing works with kwin and/or the theme engine, since they seem to expect to be able to make buttons visually overlap the resize frame but have the resize frame still work: https://bugs.kde.org/show_bug.cgi?id=513249
I’m not sure what the best way is to have this change, but it’s a real problem. Sorry if I just configured something wrong, but it seems like that’s not the cause of this. (…this time 
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