This an old problem, but providing a link to the solution below for ease of reference.

https://gist.githubusercontent.com/alexeyknorre/b0780836f4cec04d41a863a683f91b53/raw/9b667333802c149ad1f503929a81de98cb78eef7/stargazer_fix.r

## Quick fix for stargazer <= 5.2.3 is.na() issue with long model names in R >= 4.2
# Unload stargazer if loaded
detach("package:stargazer",unload=T)
# Delete it
remove.packages("stargazer")
# Download the source
download.file("https://cran.r-project.org/src/contrib/stargazer_5.2.3.tar.gz", destfile = "stargazer_5.2.3.tar.gz")
# Unpack
untar("stargazer_5.2.3.tar.gz")
# Read the sourcefile with .inside.bracket fun
stargazer_src <- readLines("stargazer/R/stargazer-internal.R")
# Move the length check 5 lines up so it precedes is.na(.)
stargazer_src[1990] <- stargazer_src[1995]
stargazer_src[1995] <- ""
# Save back
writeLines(stargazer_src, con="stargazer/R/stargazer-internal.R")
# Compile and install the patched package
install.packages("stargazer", repos = NULL, type="source")