Comment by swimmingbrain

Can't tell much from those two lines, but if you open an issue with the document, or just provide the full compile log, I could dig into it.

The TFM error usually means a font file wasn't available. However, the service worker validates the downloads before caching, so any error pages or empty bodies get rejected (which makes posoned cache unlikely), but a stale state may still be possible.

Hard refresh bypasses the service worker, I patched around that last month but apparently not well enough.

Also, better error logs and reporting is already on my ToDo-list, sorry for that.