This is a minimal, information-only view currently, listing by default
all the override data-blocks, with their user-edited override
properties.
System-generated overrides (like the overrides of pointers to other
override data-blocks) can be shown through a filter option.
Finally, potential info or warning messages from (auto-)resync propcess
are also shown, as an icon + tooltip next to the affected items.
Part of D10855.
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