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Fully support Web USB and Web Serial

Making moves

Web-based IDEs like Arduino and Github Codespaces are now commonplace. They are hobbled in Firefox due to an inability to access development boards without installing extra system software, which rather defeats the purpose of having an IDE that runs in your browser. This is not the case on Chrome, where Web USB and Web Serial can be used. (Clarification: they *could* be used on Chrome, but often are not because developers don't want to maintain two separate codebases.)

I will preempt the response I have received every previous time I brought up this topic: Web USB and Web Serial present no more of a security risk than web camera or location data, and Firefox already has a permissions system to protect those. On the other hand, the software you have to install to make Arduino IDE work in Firefox starts a webserver that shares your serial port over a websocket, just so that your browser can connect to it. It isn't clear if there are any protections at all on that websocket.

I will also note than the current prevalence of web-based development environments is in part due to Mozilla's insistence that everything should be able to run in the browser, along with projects like Firefox OS.


Making moves

I'm coding a project on Adafruit's circuit python platform and I have to use Chrome because Firefox doesn't support web serial. Very disappointed. The future of microcontrollers will rely on integration with web serial. If you could just take a look at what WipperSnapper is doing for AdafruitIO platform I'm sure you'd agree. Any microcontroller that has WiFi capability (including Raspberry Pi & Arduino) will need web serial in the future.

Firefox is lagging behind Chrome for web serial adoption to the point where people must now seriously consider using Chrome as their main browser of choice. Firefox users who play with microcontrollers don't want that and I'm sure Mozilla doesn't want that.

I agree!

Please Mozilla, add these API to Firefox 🔥🦊

Not applicable

Not a feature i would want. Also seems like api can be potentially harmful to the user. At least that seems like the current verdict. ref.

I really and honestly fail to understand this position. 1. In Chrome browser pop-up is required to show and to specifically choose which devices are available to given website. 2. Before WebSerial some websites required additional app on users machine that would act as a bridge between browser and serial device. Do you deem it's safer to install some app to act as a bridge instead of using native browser APIs? Moreover app-per-vendor which might mean A LOT of apps when user uses many of such devices. I believe it can be done properly and safely (yeah, Chrome's way is a good way, but could be hidden behind about:config), but for some reason Mozilla refuses to focus on it, forcing its users to use Chrome just for the purpose of hardware interfacing.

Making moves

I think supporting WebSerial (even if behind an about:config option to reduce attack surface for the users who don't want or need it) is required to compete in the 2023 browser market. I hate having to switch to Edge every time I need to use it.


Same here, please add this feature to Firefox. I'm the CEO of Vittascience, an education company specialized in coding for schools (especially hardware such as micro:bit and arduino). Because of this limitation, we are advising our 35k monthly active users to use Chrome or Edge instead of Firefox (which they often do).

As @domints mentionned, it is not riskier than camera, microphone or location APIs, and surely much safer than the local bridge (websocket) required at the moment (we gave up on this websocket solution after 2 years of users complaining, especially about Firewall issues in schools).

If you need, I can provide you hundreds of teachers testimonies asking for this feature on Firefox. For information, Firefox usage is much higher in the teaching world than in average, so losing this user base would have very negative consequences for Mozilla.

Making moves

Hello everybody,

I'm the project manager for Capytale, an educational service developed by the French Ministry of Education and used by over 300,000 users. More than 30% of the connections we record are on Firefox.

We plan to develop the use of hardware programming such as micro:bit and arduino and it is a pity for our users to have to change browsers every time they need to download programs via USB.
It's also very sad for the development of Firefox, which we systematically encourage students to use.

The Capytale team sincerely hopes that Firefox will soon support WebSerial.

Making moves

It should be supported, even if behind a config flag. I create dashboards for smart home using web technologies, and it's unfortunate that I have to run them in a Chrome window.