This might also pertain to other global fields. When you modify a view with some footer/header strings translated, they are lost upon save. A nightmare.

Comments

Status:Active» Postponed (maintainer needs more info)

I think this is caused by a bug in views, see #1525152-21: format_key handling broken which results in lost translations.

Please test the patch that and if you can confirm that this fixes the problem for you as well, close this issue.