I downloaded a copy made by v5.5.2. Tried to upload into a new site. v5.5.1! Updated new site to v5.6.0 and tried to upload again - this time I got:
0 Call to a member function get() on null
Updated existing (old) site to 5.6.0. Now I get a 500 error trying to export! :-) Just not my day!!!
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