Aspnetcore: Unable to Debug Blazor WebAssembly 3.2.0 Preview 3 App

Created on 10 Apr 2020 · 16Comments · Source: dotnet/aspnetcore

_This issue has been moved from a ticket on Developer Community._

The Visual Studio Debugger does not appear to work. I have no problem running apps just not able to debug in VS.
I have created a project using the template, pressed F5, set a breakpoint on the IncrementCount method and Navigated to the counter page and nothing.

Original Comments

Visual Studio Feedback System on 4/8/2020, 08:44 PM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

Original Solutions

(no solutions)

Author Needs area-blazor blazor-wasm

Source

vsfeedback

Most helpful comment

@mkArtakMSFT.

For me, debugging does not work in Microsoft Edge Version 80.0.361.111 (Official build) (64-bit) nor Firefox 75.0 (64-bit).

Everything works great in Google Chrome Version 81.0.4044.92 (Official Build) (64-bit).

LeeActon on 13 Apr 2020

👍4

All 16 comments

Thanks for contacting us.
Can you share some more details about your environment? This is not a feedback we've heard from others so would like to understand what's going wrong.

mkArtakMSFT on 10 Apr 2020

The same happens to me too. When i hover on the breakpoint (the breakpoint is in the IncrementCount method) i see this message: "The breakpoint will not currenlty be hit No symbols have been loaded for this document."

(Edit)
I have
dotnet version: 3.1.300-preview-015048
Visual Studio: Version 16.6.0 Preview 2.1

DimitrisRousis on 11 Apr 2020

I was having exactly the same issue, then I thought "maybe it's because I'm using Firefox as my browser"... so I switched to the latest Microsoft Edge and still had the same problem. Then I switched to Chrome and it works fine.

LeeActon on 11 Apr 2020

I tried with Chrome but the problem still remain.

(Edit)
I tried again and now its ok. Using chrome i can debug the app now. I dont know why the first time didn't work.
Thank you.

DimitrisRousis on 12 Apr 2020

Glad that it worked out, @DimitrisRousis.
Can you share the version number of the Edge browser, when it opens up when you start the debugging session?

mkArtakMSFT on 13 Apr 2020

@mkArtakMSFT.

For me, debugging does not work in Microsoft Edge Version 80.0.361.111 (Official build) (64-bit) nor Firefox 75.0 (64-bit).

Everything works great in Google Chrome Version 81.0.4044.92 (Official Build) (64-bit).

LeeActon on 13 Apr 2020

👍4

@LeeActon thanks for the info. The Edge version is the same as one of our team member has, and they are debugging just fine. we will look into this in our next sprint planning, as we're wrapping up Blazor WASM release.

mkArtakMSFT on 14 Apr 2020

@mkArtakMSFT
I tried on:

Microsoft Edge Version 81.0.416.53 (Official build) (64-bit)
Google Chrome Version 81.0.4044.92 (Official build) (64-bit)

With both browsers the debugger works.

DimitrisRousis on 14 Apr 2020

Thanks for confirmation, @DimitrisRousis. Glad that you've got debugging working for both browsers.

@LeeActon can you try to update to the version listed by @DimitrisRousis above (81.0.416.53) and see whether that fixes it?

mkArtakMSFT on 15 Apr 2020

@mkArtakMSFT, I updated to Microsoft Edge Version 81.0.416.53 (Official build) (64-bit), and the debugger still fails to work. Specifically, breakpoints say "This breakpoiint will not currently be hit. No symbols have been loaded for this document."

LeeActon on 15 Apr 2020

FYI, I just updated to Visual Studio: Version 16.6.0 Preview 3, and debugging now works in Edge.
It still works in Chrome, but still does NOT work in Firefox.

BTW, I'm ecstatic to be able to debug Blazor WebAssembly in VS. One working browser was good... now I have two... I can live without Firefox.

LeeActon on 17 Apr 2020

👍2

Glad that you got it working. Seems like there is no more action pending here. Closing this issue.

mkArtakMSFT on 17 Apr 2020

@mkArtakMSFT,

Ok, now I'm back to debugging not working, but now it's failing on all three browsers (Chrome, Edge, and Firefox).

It seems to be specific to my project because a simple project that is created from the standard template and unmodified works perfectly fine.

Looking at the modules that are loaded in the working and non-working scenarios, the "javascript debugger root session" and "localhost" processes are not loaded in the non-working scenario.
See the two attached images.

The source code for my application is on github at: https://github.com/SparksInTheSoftware/Sudoku.

As far as I can tell, there isn't anything different in how the working and non-working projects are built or launched.

Working:
good

Not working:
bad

LeeActon on 21 Apr 2020

Having the same issue on:

idscom on 29 Apr 2020

@mkArtakMSFT,

I updated to RC1, and I'm still unable to debug the project I posted earlier.

LeeActon on 1 May 2020

I'm having the same issue on Visual Studio Community 2019 Preview 16.7.0 Preview 1.0.
Doesn't work with any browser.

EDIT: As it turns out, it wasn't breaking for me because I was trying to break on OnInitializedAsync, which is fired before the debugger actually connects. (source: https://github.com/dotnet/aspnetcore/issues/22212#issuecomment-633935162)