SpiderMonkey Newsletter (Firefox 124-125)

Hello and Welcome to the SpiderMonkey Newsletter for Firefox 124-125. It’s Matthew Gaudet back again. This newsletter is a way in which we can share what we have been working on as a team, and highlight some interesting changes when they happen.

🚀 Performance

We have been hard at work making sure that Firefox’s performance on Speedometer 3 was excellent. With the official release of Speedometer 3 we are very happy the fruits of our labour.

Even though Speedometer3 will ship while Firefox release is version 123, that doesn’t mean that we have stopped working on performance!

Contributor Spotlight

Sometimes a contributor comes along who decides that one of the ways they can help is by taking ownership of an area, and making steady improvement forwards. This was the case with Vinny Diehl who has come in and become an expert on Date.parse. This is a challenging method, because it is simultaneously commonly used while extremely underspecified, leading to lots of implementation defined behaviour. This kind of implementation defined behaviour can be bad for Firefox, as dates that are parsed correctly by Chrome or Safari might not be parsed correctly by Firefox, leading to web interoperability problems.

Vinny has been working on improving this, and has made enormous strides in helping to push this challenging area forward. In his own words:

Vinny Diehl is a helicopter pilot who dabbles in software development and reverse engineering in his spare time. He has worked on flight simulators, game engines, and Nintendo decompilation projects, among other things. With a growing interest in browser work, he has made it his mission to perfect SpiderMonkey’s date parsing compatibility. You can view some of his work in the meta bug.

Huge amounts of gratitude to Vinny for tackling this and making Firefox more compatible for everyone.

⚡ Wasm

🕸️ Web Features Work

👷🏽‍♀️ Other Work