Installed, but doesn't seem to take effect
Up until yesterday I would have said, that sentence should be dropped. I tried it yesterday on an 1.18.3 mediawiki and it seemed to work. Can you try if it works on http://scratchpad.referata.com?
I get the same behavior as I do on my site. Maybe I'm using it wrong? I'm still copying the example: http://scratchpad.referata.com/wiki/Special:FormEdit/ActiveFormTest/Test_Page
Very good, that helps a lot. I will investigate what could be the problem and come back to you.
Sorry, it took me a while. I think I fixed this. Could you try the SFI version from https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/extensions/SemanticFormsInputs.git;a=snapshot;h=refs/changes/38/12438/1;sf=tgz and tell me if it works for you? Or if you have git installed and SFI cloned, just do a
git pull https://gerrit.wikimedia.org/r/mediawiki/extensions/SemanticFormsInputs refs/changes/38/12438/1