In both Rmarkdown and Quarto documents, inline table outputs are not displaying any characters and only display as U+FFFD or the question mark in a box, see picture.
I've run through a Sys.getlocale() and Sys.setlocal() command to set the locale to en_US.UTF-8 as well as changing the fonts and display settings in RStudio.
Current RStudio is 2025.5.1.513, Quarto is 1.7.32, and R is 4.3.3.
This may be also due to my macbook running macOS 26 Tahoe beta
I'm getting the same problem running the release version of Tahoe and RStudio 2025.09.0 Build 387. This problem is definitely Tahoe related. I didn't see it before upgrading. Tables do render correctly to PDF and/or Word. It's just the inline output in RStudio that's not working.
Several people have hit this with Tahoe (both in betas and the release version). The problem is corrupted macOS fonts. Quarto table preview text not rendering in new macOS 26 · Issue #16237 · rstudio/rstudio · GitHub has some details on how a couple of users (so far) have been able to fix this using Font Book to reinstall some fonts.
