Blank part tab name after part export or copy

After the creation of parts from a score then the saving of an individual part, the score with parts loses the tab name for the saved part.

The recreation scenario is this:
Create new score (call it test), I selected string quartet
File>parts
New All
save the new score (eg test.mscz)
Select the viola tab
save a copy (use a unique name, eg test-Viola.mscz)
open the saved viola mscz (test-vla) while keeping test open.
switch to the test tab and you should see that the viola part has lost its name.

It's the concurrent opening of the saved part and the original score that causes the tag for the viola to lose its name in the score file.

I tried this on a 3.0 build from last week but couldn't recreate it.

On examining the mscx files for the score before and after the tab name has been lost for the saved part I see that the only difference is the <name>tabname</name> tag which has become <name></name>. Editing the mscx to replace the missing tabname fixes the missing name.

It looks like there's interference between the two open files in musescore. If one closes the score before opening the saved part then open the score, the loss of tab name doesn't occur. In fact it doesn't matter which order the subsequent opens are done in once the score is closed after the part "save a copy" operation.

Richard