Thanks for the report and great screencast.  Unfortunately, I cannot reproduce this bug on 56.0.2920.0 Linux or Mac.  If you could let us know of anything special with your setup, that would help.

- Do you have any DevTools extensions enabled?
- Could you try recreating the bug in a fresh Chrome guest profile?
- It looks like you have a workspace mapping (from the orange folder 'source').  Does this split happen when mappings are disabled?
- Are there DevTools errors?  To check this, you need to undock Devtools into its own window, press Cmd-Shift-I to get DevTools' DevTools, and check that 2nd window for console errors

Adding Needs-Feedback label as per comment #1.

Thank you!

Wasn't able to reconstruct it either this morning then i got the bug.

An breakpoint has to be active(triggered) then switch between the Source and Network tab.

Did it work for you ?

ps. i'm staring chrome with:
open  -a  /Applications/Google\ Chrome\ Canary.app -F -n --args --allow-running-insecure-content --disable-web-security --user-data-dir

but i think the bug is when the debug mode is active. it works when the debug mode is not active. When i leave the debug mode the panel splitter dissapears

a new one:
http://prnt.sc/d8ruyt


thats only on canary no idea how to reconstruct it, it just happend when switching tabs

will create a new task for this

I am still unable to reproduce the bug on Mac with Canary 56.0.2924.0.  I tried opening with the same arguments in comment #4 and made sure I was paused on a breakpoint.

@OP: here's some instructions that may help you try out a fresh Chrome profile.  Please let us know if you can reproduce the bug in a guest profile.
https://support.google.com/chrome/answer/6130773

@einbinder: I cannot repro the screenshot in comment #5, but perhaps you have an idea how?

I have also issues to reconstruct it. Most of the time it works. I was also thinking it could be because of the mac fullscreen mode but no :/

Only facts:
- it happens when switching multiple times between Source and Network tab(not sure if i tried the others)
- the bug is not present in chrome stable


Will report if i figure out more about the bug.

I just saw that i have maybe some devtools experiments active:
http://prnt.sc/d9w6dn

 Issue 666673  has been merged into this issue.

@teo: next time it happens, please:
1) undock devtools to be its own window
2) press Cmd+Option+I to open devtools on devtools
3) send us console errors if any in that second window.

I think this is another bug no idea how to reconstruct it it happend in the stable chrome version, didnt had this bug before till today
http://prnt.sc/de2awg

when i click on the line number with the glitch the number for that line number moves back to the correct location
http://prnt.sc/de2cbs

ps. this happened on - stable:
Version 54.0.2840.98 (64-bit)

ps. devtools experiments active:
http://prnt.sc/de2dnk

can be because of the UI themes experiment ?

Thank you for providing more feedback. Adding requester "rbasuvula@chromium.org" for another review and adding "Needs-Review" label for tracking.

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

As per comment #14 tested the same on mac 10.12.2 chrome version 55.0.2883.87 with custom UI themes experiment enabled in devtools - Observed no issue when moving between source and network panels. Also no glitch seen on clicking any line

Please fins the screencast

Could you please upgrade to latest chrome versions and see if issue still exists. If yes please send the console errors as mentioned in comment #12

Deleted: 666243.mov 17.2 MB

666243.mov 17.2 MB Download

Closing for now as non reproducible.
If it happens again please reopen. Also please open DevTools on DevTools (just press Ctrl+Shift+I having devtools focused) and check if there are any errors in the console. Thank you.