Full calendar month view broken after update to WP 4.8.2

Hi. Since updating to WP 4.8.2, the month view of the calendar has stopped working – just shows a spinning progress gif. I noticed from researching issue that other calendars were affected also. Has anyone else experienced this issue?

I have already tried the deactivating all other plugins and changing themes. The plugin does work with the standard wordpress themes, but not on my themco Xtheme. Themco indicates that they are compatible with WP 4.8.2.

Not sure what to do/try next.

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