I don't recall seeing any pertinent errors. Just the usual warnings about "so-and-so is declared but not used" etc. (Applies to builds with either 5.9.4 or 5.12.3) Not that I was paying too much attention. I had cat sandboxes to deal with.
I don't usually edit in WYSIWYG mode, but I have this OCR nightmare (source was a pdf of a scanned typewritten -with a manual typewriter- document). It's a wonder the OCR software got anything useful at all.
Albert