Dear person who used the search terms “writing has become empty rectangle in cad” and “autocad text has become an empty rectangle” on this blog, I suspect you probably have a drawing where QTEXT has been turned on. To fix this, enter QTEXT at the command prompt, set it to OFF, and if the problem doesn’t go away by itself then issue the REGENALL command.
Pedantic note: the command name is QTEXT, but this controls a system variable called QTEXTMODE. QTEXT OFF is equivalent to both SETVAR QTEXTMODE 0 and just QTEXTMODE 0. In LISP it would be (setvar “QTEXTMODE” 0).
This tip applies to all AutoCAD releases and variants you’re likely to run. Because BricsCAD has a high degree of command-line compatibility with AutoCAD, it applies to BricsCAD too. The same may apply to other AutoCAD-compatible applications.
I recently had a problem with block attributes showing as rectangles instead of text in a PDF output (made with dwg2pdf.pc3 in AutoCAD 2018 and viewed with PDF X-Change). I solved it changing EPDFSHX to 0. Full explanation here :
https://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/PDF-created-from-AutoCAD-shows-frames-around-text-in-PDF-viewer.html