Thanks for the report and for the video, much appreciated. Unfortunately, I am unable to reproduce the above issue on Mac 10.11.4 with chrome version 50.0.2661.87(Stable), 52.0.2017.0(canary). 

I would request you to please try the above issue on latest chrome version '50.02661.87' and let us know if the issue still persists.

Attach is the screen case for the same.

Appreciate your help.

Thank you!

Deleted: Retest -606650.mp4 1.4 MB

Retest -606650.mp4 1.4 MB Download

I have the same problem on Chrome 50.0.2661.86 and 52.0.2017.0 and had it for a while now.
I removed all my extensions as you can see in the gif. I asked around as well and seems like I am the only one with this problem so I guess it's local but have no idea how to fix it.

Deleted: chrome_devtools_zoom.gif 1.4 MB

	chrome_devtools_zoom.gif 1.4 MB View Download

Thank you for providing more feedback. Adding requester "ashejole@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

Unable to reproduce this issue on Mac OSX 10.11.4 - 50.0.2661.86 [Stable] and 52.0.2517.0 [Canary] as well.

oldering@, please let us know if you are using a retina machine ?

Yes I am, here are the info

OS X 10.11.4
MacBook Pro (Retina, 15-inch, Mid 2015)
Processor: 2.8 GHz Intel Core i7
Memory: 16 GB 1600 MHz DDR3
Graphics: Intel Iris Pro 1536 MB

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

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Unable to reproduce the issue on Mac OSX 10.11.4 [mac book Pro] Retina - 50.0.2661.87
GPU --> Intel HD Graphics 4000 Open GL Engine.

Seems like a GPU specific issue as the reporter's able to reproduce the issue on Intel Iris Pro GPU card.

Can you please try disabling all extensions and/or try in incognito mode. We are still unable to reproduce.

I tried already with both options (on the 2# comment, you can see I disabled all extensions) but the same result remains.

By the way, I can zoom in inside dev tools only if if I move it into its own window (undock into separate window).

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

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Cmd-+ works fine in the DevTools pane for me with 52.0.2722.0 (Official Build) canary (64-bit) on OS X 10.11.4.

Removing GPU related fields until it's been demonstrated that this is a GPU-specific issue and not caused by installed extensions or something similar.

@oldering: Could you please respond to the comment #12.

Thank you.

@mimmagadda Sorry, I don't see question or guidance about things to do in #12.
What else should I test ?

The only thing I can come up with on why this is happening is if a key on the keyboard is being sticky or another program interfering. On windows this can happen if the "windows key" is held while ctrl it will zoom the web page, but if just ctrl is pressed it will zoom devtools.

Unless we can reliably reproduce this issue, I don't see how we can fix it.

Tested on below platforms: Cmd-+ works fine in the DevTools pane for me and unable to reproduce the same .

Ubuntu 14.04 LTS chrome version 50.0.2661.102 
Win 7 64 bit/Mac 10.11.5 chrome version 51.0.2704.63 & 53.0.2749.0 canary
Win 10 53.0.2749.0 canary

oldering:could you please confirm whether you are seeing the issue or not on latest chrome version?
Thank you.

I still have the same problem on Chrome 51.0.2704.63 (64-bit) and 53.0.2749.2 canary (64-bit).

As for #15, I tried again after removing Seil but did not change the result.

Is there no way I could trace why it is happening as so?

Could you supply us with a tracing profile from: chrome://tracing/ and select Frame Viewer after you hit record.

(There may be sensitive information in here so only send it if you are ok with us receiving this info. You may email it directly to me.)

Thanks

@allada: sadly, I don't think trace is of any help here.

oldering@ Can you please try this on the latest version of Canary and see if the issue still persists?

@allada: still the same with 54.0.2804.0

Is the tracing thing still useful?

Happy to see I am not the only one.

https://groups.google.com/forum/#!topic/google-chrome-developer-tools/xKGbUSgsQio

I am not sure what's happening here, can you tell us what OS exactly you are using, which device it's on (and year) and what language/keyboard settings you are using?

It happens on both my MacBook Pro (MBP) and my MacBook Air (MBA), both have a japanese keyboard. The only setting I changed is to have Control on the CapsLock key.
And it still happens on the latest Canary 55.0.2873.4 64 bit

MBP:
OS X 10.11.6
MacBook Pro (Retina, 15-inch, Mid 2015)
Processor: 2.8 GHz Intel Core i7
Memory: 16 GB 1600 MHz DDR3
Graphics: Intel Iris Pro 1536 MB

MBA:
OS X 10.11.6
MacBook Air (13-inch, Early 2015)
Processor: 1.6 GHz Intel Core i5
Memory: 8 GB 1600 MHz DDR3
Graphics: Intel HD Graphics 6000 1536 MB

Cleaning up "Needs-Review" label as we are not using this label for triage anymore. Ref bug for this cleanup 684919

I am going to close this bug to get it out of the queue. If you still see this occurring please feel free to open a new issue.

Thanks.