You are currently working on UAT 

Under Community Review

The Online Editor currently supports this behaviour but the limitation is imposed by the Claim function in WorldServer, as each Task can only have a single Claimant. We would need to loosen this requirement in order to support concurrent editing. Further, we would need to implement a means of measuring which segments (and its word count) had been translated by each Claimant.

Lock segments assigned to translator A when translator B is working on the same SDLXLIFF in WS

This is a suggestion for a collaborative function in Online Editor.