As discovered by Nadav Kavalerchik, this is a regression of recent AMOS storage migration.
- Let's have a component like qtype_geogebra with 2.7+ strings
- The users imports translations and selects latest version 4.0+ during the import
- Translations are backported so there is: 2.7+ original, 4.0+ translation and 2.7+ backported translation.
At this moment, AMOS does not allow to edit this 2.7+ translation easily, if at all.