multi-object editing of mixed values, and pressing Escape after modifying their property fields

I'm seeing an issue with pressing Escape in mixed value property fields after editing those fields. To repro:

1) select multiple objects with mixed values for, say, a float property
2) put cursor into the float field for that property and type in a different number without pressing Enter to confirm
3) press Escape

Result: value gets set to 0 for all of the objects.
Expected: value gets reset to what it was on each individual object (same as when just a single object is selected).

Note: if I select multiple objects and go through the same steps, but the value is not mixed, the values are properly reverted everywhere (e.g., if they're all 1 to start, I type 2 and then press Escape, they all get set back to 1)

Is there a way around this via a custom inspector? Also, I'm not on the bleeding edge version of Unity, is this fixed in a recent version?