NOTE: Issue has been identified and a patch has been merged that should fix the issue. Currently waiting for deployment. **To fix pages that have incorrect content, please mark the pages for translation again after the fix has been deployed.**
== Steps to reproduce
# Have a(n at least partially) translated page.
# Make some changes to its original and mark it for translation again. (Changes are not strictly necessary to reproduce, but they make clearer what happens.)
# Look at the formerly translated page.
== Actual result
4. The translation template’s changes are applied, but all translations are replaced by the original texts (properly marked up in syntax version 2).
== Expected result
4. The translation template’s changes are applied, //and// existing translations are preserved.
== Other info
* New regression in 1.37.0-wmf.18.
* Examples: [[https://commons.wikimedia.org/w/index.php?title=Template:File_renaming_reasons/i18n/de&diff=579836995|Commons]], [[https://meta.wikimedia.org/w/index.php?title=Meta:IP_block_exemption/de&diff=21871651|Meta]]. A mark for translation [[https://meta.wikimedia.org/w/index.php?title=Template:WMF_Staff/hu&diff=21871248|earlier today]] (i.e. before the train arrival) was still fine.
* Marking for translation removes all of the translation, people can’t read pages in their native languages.