What do you think?
Looking at raw numbers of cve reports, FF is doing better than chrome:
https://www.cvedetails.com/product/3264/Mozilla-Firefox.html?vendor_id=452
https://www.cvedetails.com/product/15031/Google-Chrome.html?vendor_id=1224
But the severity of those reports is another matter. One single report could make a night and day difference.