Intention:
Move a sentence to a diffeent place on the page.

Steps to Reproduce:

1. In Firefox, open a page containing existing [[links]] to other pages on the wiki.
2. Cut one of them.
3. Paste it in a different spot.

Actual Results:
The link gets converted from [[Link]] into [http://en.wikipedia.org/wiki/Link].

See https://en.wikipedia.org/w/index.php?title=User:Edgepedia/VE/S%26D&diff=588724142&oldid=588539903 and https://en.wikipedia.org/w/index.php?title=Silaum_silaus&diff=588803158&oldid=587979575

Expected Results:
The [[Link]] would remain an internal link.

Reproducible: Sometimes

One of these pages involved the {{sfn}} (shortened footnotes) template.

Version: unspecified
Severity: normal