Sorry, a clarification based on more testing. This happens when a long line which causes wraparound in the Terminal is pasted into a Gmail message.

It can be worked around by selecting all of the text and clicking the "Tx" button to remove all text formatting.

I'd assume the Terminal's text is unstyled and that it shouldn't be necessary to use "Paste and match style" when pasting from it.

While I think this is a somewhat recent regression, it's happening in Chrome Stable ( at least 54.0.2840.98 (Official Build) (64-bit)) so maybe I'm misremembering.

I don't repro on macOS 10.12.2.
Do you have specific text to paste?

Sure, here's a random line from my terminal:

ls content/test/gpu/gpu_tests/png_test_data.py.OBSOLETE content/test/gpu/gpu_tests/test_png.py.OBSOLETE content/test/gpu/gpu_tests/unity.py.OBSOLETE content/test/gpu/generate_buildbot_json.py.new

Actually, I just realized it happens even with a line that doesn't wrap around. It's probably related to the font used in the terminal. Just repro'd on 10.12.2. See screenshot.

Deleted: Screen Shot 2017-01-12 at 9.29.24 PM.png 292 KB

	Screen Shot 2017-01-12 at 9.29.24 PM.png 292 KB View Download

Tested the issue on Mac 10.12.2, windows-7 and Linux Ubuntu-14.04 using chrome stable version 55.0.2883.95 and canary 55.0.2883.95 with below steps.
1.Opened Chrome and Compose an email in Gmail
2.Copied the text from Terminal(given in comment#3) and pasted it into email and continued typing.
Not Observed double space in the text.
Please find the attached screen-cast and please let us know if anything missed here to reproduce the issue.

Thanks..
 

Deleted: Mac-673562.mov 3.4 MB

Mac-673562.mov 3.4 MB Download

What font is set in your Terminal on macOS? Mine is set to "Menlo Regular 11 pt." per the screenshot above. I think that's what's causing the double-spacing.

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

Able to reproduce the issue on Mac Retina 10.12.2 (Terminal font-"Menlo Regular 11 pt.")and Linux Ubuntu-14.04 using chrome stable version 56.0.2924.76 and canary 58.0.2997.0 with the steps mentioned above.
This is Non-regression issue, observed from M30 # 30.0.1549.0.
Note:In M30 observed the space in all lines.
From M40 to M56 observed the space in 1st and 3rd lines.
From M57 to M58 observed the space in all lines.
Issue not observed in windows-7 .

Thanks..

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