Dolphin Previews not cached

As of today Dolphin is not caching previews in ~/.cache/thumbnails. I am experiencing this behavior on three machines so wonder if an update has broken something?

It might be worth mentioning that the folders in question are all LUKS encrypted.

Has anyone else experienced this, and ideally have a fix?

The LUKS encryption is significant. It seems Dolphin caches previews to /~/.cache/thumbnails and hence doesn’t save the previews of encrypted volumes as it would be a potential security issue.

If anyone can think of a workaround I would be most grateful.