There is one separate JS context for every tab you have opened right now and every feature has its cost in terms of memory & cpu. That's a major reason why java

There is one separate JS context for every tab you have opened right now and every feature has its cost in terms of memory & cpu. That's a major reason why javascript has very thin "stdlib". Also, big stdlibs are compatibility problem so it's definitely better to have as much as possible in user-space. BUT, we really should use few big utility libraries like lodash instead of dozens of helper-function modules.