Allow (or switch to) generating html that starts with <!doctype html> when using to_html(full_html=True) #4847
Description
Currently, plotly.py's to_html() function (when using the default full_html=True argument) generates html that doesn't start with a required doctype (i.e. <!doctype html>). It would be good to support this, or switch to doing this.
The code can be found here:
plotly.py/packages/python/plotly/plotly/io/_html.py
Lines 343 to 352 in 095d2d8
The reason I noticed this is that some plots I'm working with were formatted differently when I used full_html=False to include a plot into another html document that did start with <!doctype html>. I narrowed the reason for this difference in formatting down to the presence or absence of that single line. Since plots can be included into html with or without a doctype, it would probably be good to be aware of this difference.