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Firefox Replay

firefox-replay.com

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Re: Firefox Replay

#251

Post by jasonlaster11 »

rckclmbr wrote: post #232
jasonlaster11 wrote: post #194

Earlier quoted context omitted.

Team member here. Firefox Replay is currently in user research phase while we validate it. Cross platform support will absolutely be a priority when Replay is on the official roadmap. Thanks for the feedback, firefox-replay.com is also a work in progress. We did not plan an official release today. We'll be sure to make the Mac OS limitation more clear. Here is some more context on the mac specific functionality ( htt…

> Firefox Replay is currently in user research phase while we validate it A question about how you develop / roll this out. Do you keep the code private, or do you commit it to the open source repo as you're working with a small amount high touch users? I guess the question is do you want a full working product when you open source it? Do you tie your PR / forum posts with publicly shipping the source code? Or is all…

Good question.

Everything is in firefox and open source

Here are the bugs: https://bugzilla.mozilla.org/buglist.cgi?cmdtype=runnamed&na...

Here's the primary directory: https://searchfox.org/mozilla-central/source/toolkit/recordr...

The debugger API is implemented in JS here https://searchfox.org/mozilla-central/source/devtools/server...

Re: Firefox Replay

#252

Post by jasonlaster11 »

ken wrote: post #243
hbosch wrote: post #198

Earlier quoted context omitted.

Actually probably Mozilla’s largest user base

Why 'probably'? According to the stats I could find [1], Firefox has around 5% of Mac users, and around 9% of Windows users. Windows is Firefox's biggest platform, both in absolute terms and as a fraction of that platform's users. On Linux, Firefox has a bigger percentage (>30%), but (desktop) Linux is much less popular than macOS so in absolute terms they have the fewest users there. [1]: https://netmarketshare.com/

The plan is to do user testing on mac and if it is validated roll it out.

Replay requires a ton of difficult platform-level investment to get right and we're still actively finding bugs in the real world.

After it is validated, it will be easier to add the appropriate platform level bindings in other OSs.

Re: Firefox Replay

#253

Post by jasonlaster11 »

glassounds wrote: post #219
kevsim wrote: post #6

The biggest benefit for me (I think) would be if the product/design people I work with could find issues and send their recordings to me. Don't think I'll be able to convince them to switch to FF though.

https://birdeatsbug.com is great for that kind of thing

Very cool. The product looks great!

Re: Firefox Replay

#254

Post by tropo »

jasonlaster11 wrote: post #189
BoppreH wrote: post #90

Earlier quoted context omitted.

Sounds like Mozilla is applying the concepts they developed for their C/C++ debugger, rr ( https://rr-project.org ).

That's exactly right Brian Hackett collaborated early on with ROC. Here are the basic principles of Replay ( https://developer.mozilla.org/en-US/docs/Mozilla/Projects/We... ). In a nutshell, replay records Firefox's OS system calls, so that that Firefox can read from the recording when replaying.

This seems to mean that a recording done on x86_64 MacOS can't be played back on aarch64 Linux, which is a shame for something that apparently is for javascript debugging. Limitations like that are more understandable for rr, which is intended for use with native processes.

It also looks like a maintenance burden which will increase the difficulty of supporting an OS for Firefox. Stuff like that causes Firefox to drop support for an OS, and it makes developers hesitant to add support for an OS.

System calls can do all sorts of crazy stuff behind your back. Think of ioctl and fcntl. Just knowing what memory they modify is difficult. It's been lots of trouble for tools like strace and rr. Hopefully you won't encounter worse, like vfork and clone.

Re: Firefox Replay

#255

Post by sincerely »

Terretta wrote: post #245
bsamuels wrote: post #234

Earlier quoted context omitted.

you can virtualize linux, you cannot virtualize macos. no, downloading sketchy images or hacking your virtualization software does not count.

> you cannot virtualize macos. You can, and it’s licensed to. Since Lion: > (iii) to install, use and run up to two (2) additional copies or instances of the Apple Software within virtual operating system environments on each Mac Computer you own or control that is already running the Apple Software. No hassle support page on VMware site: https://kb.vmware.com/s/article/1000131 EDIT: Amusingly on topic with gist of t…

Well if you can only virtualize it on a computer that's already running macos I don't know how that's supposed to help.

Re: Firefox Replay

#256

Post by dustingetz »

jasonlaster11 wrote: post #250
gnufx wrote: post #231

Earlier quoted context omitted.

For what it's worth, the DMTCP [1] user-space checkpoint/restore system does that (and more). C/R is a way of doing coarse batch-based reversible debugging, typically of distributed HPC programs, and FReD [2] is a(n unfortunately dead) reversible debugger using DMTCP record/replay. 1. http://dmtcp.sourceforge.net/ 2. https://arxiv.org/abs/1212.5204

From a user perspective, we are trying to focus less on rewind and step back and more on adding logging retroactively. The best way to think about this is when the user adds a logpoint, they'll immediately see the logs in the console. We hope that making logging much better is a great way to help people better understand the recording.

adding log statements retroactively - that's awesome

Re: Firefox Replay

#258

Post by Karupan »

This will be an absolute game changer for web development. I am currently working on a really simplified version of this, but as a chrome extension. We deal with a lot of real time data and have been facing some timing issues (network and user input) which is really hard to reproduce.

I’m going to give this a shot today!

Re: Firefox Replay

#259

Post by varenc »

dessant wrote: post #239
darshan wrote: post #238

Mods: the link should perhaps be changed to: https://developer.mozilla.org/en-US/docs/Mozilla/Projects/We... This currently has 1215 points, and the link is no longer valid. It now just shows an image of Firefox's devtools and the sentence "Replay is an early experiment. We'll let you know on @FirefoxDevTools when it's ready for input." That's not useful, interesting, or informative. The MDN docs seem like an appropr…

The initial version of the site gave a good overview of Firefox Replay: https://web.archive.org/web/20191128111509/https://firefox-r...

Note: You can try out Firefox Reply on a macOS in Firefox nightly: https://www.mozilla.org/en-US/firefox/channel/desktop/

Firefox removed the content that tells you this. It's odd that they did that...

My guess is that all this attention was a premature launch, and they were hoping to make news with Firefox Replay later. (US Thanksgiving day isn't exactly ideal...)

Re: Firefox Replay

#260

Post by francasso »

Terretta wrote: post #245
bsamuels wrote: post #234

Earlier quoted context omitted.

you can virtualize linux, you cannot virtualize macos. no, downloading sketchy images or hacking your virtualization software does not count.

> you cannot virtualize macos. You can, and it’s licensed to. Since Lion: > (iii) to install, use and run up to two (2) additional copies or instances of the Apple Software within virtual operating system environments on each Mac Computer you own or control that is already running the Apple Software. No hassle support page on VMware site: https://kb.vmware.com/s/article/1000131 EDIT: Amusingly on topic with gist of t…

I wish so much I had the ability to downvote
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