Insert Close Tag: too big quantifier in {,} #17

I work with very big XML files (+43k lines). The Insert Close Tag command fails in these documents with the following error

Insert Close Tag:18: too big quantifier in {,}: /(.*\n){43881}.{4}/ (RegexpError)

It looks like rails supports this quantifier up to about 32k lines. I tried to chop of the first lines of the document, but it looks like this fails because of the way the remaining document is scanned.

I think this has to be rewritten, to scan for open tags beginning from the end of the document until it finds the first tag that is not closed already.