What happened here? I want my dimensions back!!!

Thie preview shows the dimensions saved in the file. It worked before the upgrade. See the thumbnail on the right.

When end I open the file, the dimensions are shown for half a second, then a prompt flashes "Rendering" and the dimensions disappear.

See below.

Is there a new setting for dimensions' visibility, or is this a new regression?

Using iOS 10 on iPad Pro 9.7.