Is it perhaps time to flip the default for the html5 to 1? What criteria should be used to answer that question? With smcv's last major change in this area, back in 2014, the market share of IE8 and earlier was a concern at 5%. What is the equivalent market share today?

The templates are still a real complex mess of branches around this configuration option. I'd love to see all that branching removed. Would anyone else? A hypothetical future html4 option/plugin could work by post-processing the generated output and replacing the troublesome tag names (via XSLT perhaps, depending on tooling). Is there any appetite for this?

—Jon, 2020-10-05