> In on case, I even saw a code failing because the behavior of mathematical operators with floats have changed over time I didn't know about this. Do you have

> In on case, I even saw a code failing because the behavior of mathematical operators with floats have changed over time I didn't know about this. Do you have a source or explanation? (by the way, all numbers in JS are double-precision 64-bit format IEEE 754-2008 numbers so you mean they actually changed the operators?) > A lot of breakage happen due to browser API security policy changes, obsolescence of browser APIs Non-standard features, yes. Standard features? Rarely (like WebSQL, opening HTML data URLs directly from code and so on). Standard features with wide adoption across browsers? I have just one case because of the recent CPU bugs. Standard features with wide community adoption? Never.