What did you do? ================ 1. Launched my site for testing 2. Opened Developer Tools 3. Used the Console to view log statements and view possible errors What happened? ============== - Experienced slow Developer Tool reactions (Scrolling and switching between panels) - Firefox Developer Edition window displays as 'Not Responding' - An unresponsive script window appears [Script: resource://devtools/shared/bas.../client/shared/vendor/react.js:8009] What should have happened? ========================== I should be able to use the developer tools to troubleshoot my website without the tools crashing the browser. Is there anything else we should know? ====================================== My site, although in develop state, works smoothly when the developer tools are not displayed. I originally thought there was an issue in my site, but I'm not using react in my code.

System Info: - Windows 10 Pro - Processor: Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz 2.59GHz - RAM: 16.0 GB (15.9 GB usable) - Type: 64-bit OS, x64-based processor

Developer Tools were working prior to the recent update. As recent as yesterday 9/21/17.

Could you please link to a page that causes this hang or give some more details how to reproduce it?

1. Clear Browser Cache (Everything) 2. Pull up developer tools (Ctrl + Shift + k), Console is fine 3. Navigate to https://develop.ignitorlabs.com 4. Login as demo user: Email: guestReg2@ignitordev.com Pass: efkx4b 5. Use the navigation bar to navigate to Library 6. When on the library click on the 'Featured Item - Ignitor Labs: Tech Foundations Program' 7. Scroll down the page 8. The developer tool panel begins to hang, and navigation between developer tool tabs is sluggish 9. While attempting to Performance Monitoring, the window shows 'Not Responding' While I was logged in under my personal account, the tools crash completely (My account has more permissions across the site). I received this unresponsive script message while building these instructions: Script: resource://devtools/shared/bas…/client/shared/vendor/react.js:1792

Thank you for these detailed instructions. I was not able to get the slow script dialog, but I did definitely notice a big slow down when scrolling down the page in step 7. Both DevTools and the page were both frozen for a few seconds. This seems to be linked to a large amount of log messages being logged in the console. It looks like generating these messages in the console is the cause here. After the messages had appeared, my browser and DevTools became responsive again.

It's strange since I have changed nothing between FireFox Dev versions and now it is responding slowing and crashing from time to time. I'll comment out some of the console logs and see what happens.

I'm guessing this should move to the console component.

Steps to reproduce from Comment 5 does not work anymore (page has an error). ruttech could you tell us when it's back on ? Ideally we'll record a profile so we have a reference of what is going on

Hopefully the uplift of Bug 1401972 will help. Since you're talking about scrolling that might be something we fixed in the new reps bundle.

Hello Nicolas, The Develop site is up and operational when I went to test it. I did do some updates to the code yesterday that removed a bunch of the log loops that I used to put the page together. Our production environment removes these logs, so I haven't noticed any issues there. Please let me know if there is anything else you need.

It sounds like this may have been fixed by Bug 1401972 (and uplifted to beta). Will keep this open until we can confirm.

Hey ruttech, could you check if you still see this issue in latest Beta (57.0b4), we landed a fix that might have resolved the issue and it would be really nice if we can say that it was similar to what you were experiencing

I will activate a few more of the console logs and see once if anything is amiss. I will let you know.

(In reply to Nicolas Chevobbe [:nchevobbe] from comment #13) > Hey ruttech, could you check if you still see this issue in latest Beta > (57.0b4), we landed a fix that might have resolved the issue and it would be > really nice if we can say that it was similar to what you were experiencing Hey Nicolas, Where can I update to 57.0b4? I've downloaded the newest from the website and I still have version 57.0b3.

hello, if you click on the "About Firefox" menu item, it will say there's a new version and you'll be able to download it.

Nicolas, I have done that, but no new version was downloaded. I'm still on version 57.0b3. I even downloaded and installed a new version from the website, still version 57.0b3.

Hello ruttech, https://www.mozilla.org/en-US/firefox/channel/desktop/ has 57.0b5, could you try with it please ? Much thanks !

Nicolas, I have downloaded and installed 57.0b5. After adding some of the console log statements back into my code, I was still able to get the Developer Tools to crash.

I have attached the most recent error message.

Thanks a lot ruttech ! would it be possible for you to re-enable https://develop.ignitorlabs.com/ so we can profile what's going on ? Or if not, would you be able to record a profile by yourself with https://perf-html.io/ and share it here ?

Nicolas, I am attempting to capture and upload data via perf.html. However, it is taking a lot of time to upload the profile, more than 5 minutes. Also when searching for the add-on in the 'Add-ons' panel, it was not there, is this fully supported by the newest Firefox version?

it should be, i know sometimes the symbolication fails, or maybe the profile is large. can you re-try with a shorter timespan maybe ?

I'll try capturing a shorter span. As for now, this is the error I'm getting in the console window. TypeError columnNumber: 27236 fileName: "https://perf-html.io/5d4624f85399a032f4d6.bundle.js" lineNumber: 25 message: "e.meta is undefined" stack: "r@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:27236\nw@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:97066\ne/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:15933\nr@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:258781\nu/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:259828\ns/</e[t]@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:258957\nr@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:22258\nr/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:22358\nO/</<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:265971\nO/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:265841\nu@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:269709\n" __proto__: {…} constructor: function TypeError() message: "" name: "TypeError" stack: "" __proto__: Object { … } Root.js:183:10 Unhandled promise rejection TypeError columnNumber: 27236 fileName: "https://perf-html.io/5d4624f85399a032f4d6.bundle.js" lineNumber: 25 message: "e.meta is undefined" stack: "r@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:27236\nw@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:97066\ne/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:15933\nr@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:258781\nu/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:259828\ns/</e[t]@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:258957\nr@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:22258\nr/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:22358\nO/</<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:265971\nO/<@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:265841\nu@https://perf-html.io/5d4624f85399a032f4d6.bundle.js:25:269709\n" __proto__: Object { stack: "", … } es6.promise.js:117 Successfully compiled asm.js code (loaded from cache in 20ms) zee-worker.js

I am being said you might see an older perf-html version. could you try to reload ? sorry about all this, and thanks for helping us !

I'm trying to upload a shorter capture right now. I'm still having long upload time though. If this fails, I'll restart Firefox and try again with the shorter time frame.

sounds good, if it fails again, come and talk in our slack https://devtools-html-slack.herokuapp.com/ so we can figure this out !

You may need to give me a moment, I have a demo I need to give at 10am central.

sure, no worries

Nicolas, Do you have some time to go over the perf issues?

(In reply to ruttech from comment #31) > Nicolas, > > Do you have some time to go over the perf issues? I worked with some of the guys on the Slack channel, looks like the profiler is messed up. I will not be able to record using it.

(In reply to ruttech from comment #32) > (In reply to ruttech from comment #31) > > Nicolas, > > > > Do you have some time to go over the perf issues? > > I worked with some of the guys on the Slack channel, looks like the profiler > is messed up. I will not be able to record using it. This bug was already triaged by the console team this morning and tagged high priority.

After a few hours of debugging I was able to save something to my desktop. Here is the uploaded data: https://perfht.ml/2yZGhXT