Unable to reproduce this issue on Windows-10 using chrome latest stable #59.0.3071.115 by following steps mentioned in the original comment. Observe the break point stays and doesn't disappear while refreshing the page.

mike@ Are you able to reproduce this issue on incognito mode as well? Please recheck this issue by creating a new profile under chrome://settings with no apps pr extensions in your browser.

Thanks!

Yes, I was able to repro it in incognito mode.

Please see this project:
https://github.com/spottedmahn/active-directory-b2c-javascript-msal-singlepageapp/tree/chrome-breakpoints

It must be something with the way this project is coded/configured.

Thank you for providing more feedback. Adding requester "brajkumar@chromium.org" to the cc list and removing "Needs-Feedback" label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

repro steps

-start app as described in the readme
-set a breakpoint in msal.js at line 1701 (var frameCheck = frameName;)
-click login
-login with your provided of choice
-the page will refresh and the dev tools will stop at the breakpoint but the icon won't be there

I run example but instead of msal.js - I can see minified msal.min.js. I think that I need to pass something like debug_build somewhere. Could you please point where I need specify debug flag?

Thanks for the reply kozyatin.  I'm not sure how that could be.  In, index.html there is the script tag for the un-minified version.  Are you sure you cloned this project?  https://github.com/spottedmahn/active-directory-b2c-javascript-msal-singlepageapp/tree/chrome-breakpoints

I forked this project from a Microsoft sample and the readme will still have their project not mine.  I suspect that is what happened.

https://github.com/spottedmahn/active-directory-b2c-javascript-msal-singlepageapp/blob/chrome-breakpoints/index.html

    <script src="msal.js"></script>
    <!--<script src="https://raw.githubusercontent.com/AzureAD/microsoft-authentication-library-for-js/master/out/msal.js"></script>-->

@kozyatin were you able to repro it?

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0e4ade6da647251e91094be95f952ebada19ce03

commit 0e4ade6da647251e91094be95f952ebada19ce03
Author: Alexey Kozyatinskiy <kozyatinskiy@chromium.org>
Date: Fri Oct 13 07:00:33 2017

[DevTools] update location on stub UISourceCode removed

.. otherwise it's possible for locations to stuck with :sourcemap url
if sourceMap failed to attach.

R=lushnikov@chromium.org

Bug:  chromium:740387 ,  chromium:707585 
Change-Id: Ic45f789c1bb9b73494de9f53ab3d02b14a398bd9
Reviewed-on: https://chromium-review.googlesource.com/717478
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Andrey Lushnikov <lushnikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508628}
[add] https://crrev.com/0e4ade6da647251e91094be95f952ebada19ce03/third_party/WebKit/LayoutTests/http/tests/devtools/sources/debugger-breakpoints/restore-locations-for-breakpoint-with-broken-source-map-expected.txt
[add] https://crrev.com/0e4ade6da647251e91094be95f952ebada19ce03/third_party/WebKit/LayoutTests/http/tests/devtools/sources/debugger-breakpoints/restore-locations-for-breakpoint-with-broken-source-map.js
[add] https://crrev.com/0e4ade6da647251e91094be95f952ebada19ce03/third_party/WebKit/LayoutTests/http/tests/devtools/sources/resources/a.js.map
[modify] https://crrev.com/0e4ade6da647251e91094be95f952ebada19ce03/third_party/WebKit/Source/devtools/front_end/bindings/CompilerScriptMapping.js

cool, thanks for the udpate.

I finally reproduced issue - thanks for great report and fixed it. Fix should be available in one of the next Canary.

Issue is interesting since dev server first time returns source map and on following requests after reload return 404 for source map.

Sweet!!  Thanks!