user-select does need some improvements in browsers, but this MDN page is somewhat out of date. It is now being standardized: https://drafts.csswg.org/css-ui-4

user-select does need some improvements in browsers, but this MDN page is somewhat out of date. It is now being standardized: https://drafts.csswg.org/css-ui-4/#content-selection https://drafts.csswg.org/css-ui-4/#content-selection Browsers haven't fully converged yet, but at least we're starting to see what they are likely to converge to.