In Trados Studio 2019 I checked both ways:

• With the Community Advanced Display Filter, ensure you select Locked and press the Apply button and actually see only the locked segments. Only then, save the SDLXLIFF.
• Toolkit plugin works for me as well , I mean, I get a XLIFF with only the locked segments (I checked that with an Editor).

The problem is that I CAN’T RE-OPEN these 2 new SDLXLIFF's in Studio:

- If I try to translate anyone of them as single document, I get the error Root element is missing. It’s weird because I can see the root element in the XLIFF (I believe it’s xliff).

- If I try to add anyone of them to my project, I get the error Corrupt file: Missing sub-segment content trans-unit with ID: 43981-XXX-XXXXXXXXXX

So I can create XLIFF’s, but can’t use them, and I think it worked a few weeks ago…

PS.: I checked that these 2 plugins and Trados Studio 2019 are up-to-date.

Both methods work after installing the latest update of the Community Advanced Display Filter in Trados Studio 2019:

https://appstore.sdl.com/language/app/community-advanced-display-filter/849/

can't, but you can display all the unlocked segments in edtior, select the first segment, press CTRL and click the last segment, copy the selected segments and paste them into excel or world...