Folder-scale Gotenberg, not twenty tabs
LibreOffice is CPU-heavy. Running it in parallel on a laptop tab is how sites freeze. Pro workers exist so Edge is only the control panel. This is still not OCR and not Instant-local — each file uploads, converts, deletes.
Group before you queue
Wide ledgers together (landscape). Invoice templates together (portrait). Mixing them in one job forces a bad orientation on half the set.
Failures in a batch
Corrupt .xls, passwords, and exotic macros fail that item. Fix or skip; do not assume the whole folder died.
After the PDFs return
Spot-check two files. Merge if a reviewer wants one packet. Compress if mail still rejects the pile.