We've been watching this in our office the last few days and it does not happen with newly inserted instances.
Our last big audit of details was when AC18 came out and we changed a bunch of the linework plates/beams we had to the DET_Lumber object. Our template has since been migrated to AC19.
For the error to happen it needs to have been migrated forward and originally inserted with Wood Style as Finish (as opposed to Blocking or Continuous).
They used to display correctly. In fact, they show correctly for an instant until updated.
I did update Java this morning, per another thread, and had hoped it would fix the issue - but, alas, it didn't. I'll have to send our intern through our detail library once again to fix all the instances.
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