And for Firefox Developer Tools, we have the Scratchpad. I like ours better due to the keyboard shortcuts for eval/display/inspect/re-eval function/etc, but I m

And for Firefox Developer Tools, we have the Scratchpad. I like ours better due to the keyboard shortcuts for eval/display/inspect/re-eval function/etc, but I may be biased ;) https://developer.mozilla.org/en-US/docs/Tools/Scratchpad https://developer.mozilla.org/en-US/docs/Tools/Scratchpad Much of the new JS that I write these days starts as a scratchpad that I evolve over many iterations, right in the browser.