problem

The exported SDLXLIFF can not be reimported in studio if the changed content contains locked tags and the locked content exists multiple times in the imported SDLXLIFF.

reproduction

The following situation must be given:

1. The task must be a review task
2. The task must contain multiple transunits, containing the same tag used as locked content in other segments (see screenshot import.png and the zip file in the linked TS issue)
   
3. In a segment containing the locked tag content, such tag must be moved while review
   
4. The task must be exported with SDL diff markup to trigger the problem

solution

According to the file test1.xml_mit_aenderungen.sdlxliff attached to the TS Issue, a referenced locked item (transunit mid) may not be reused multiple times. Instead the corresponding transunit must be duplicated, with a new lockTU_ ID, and this new TU must be referenced in the added tag. The old one should be referenced in the deleted tag.

Also I assume that apart from the missing new locked TU we have a problem in referencing locked items in diff export, since always the first one is referenced in the current code.