Tested the issue on windows 10 & 7 using M58 #58.0.3029.110 and issue is not reproduced using the below steps :

1. launched chrome and selected the text with mouse click and able to select the text left or right and entire page was not selected.

Attached screencast for reference.

@makedir-- Could you please check attached screencast and provide us the .mp4 file as we cannot open the provided .flv file.

Thanks!

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Are you nuts? It even happens in your own video at 0:07 ... this site is unbelievable.

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

this is truly amusing... the first two "examples" in your video arent in the category of this problem, and then the third one is, and it totally happens the moment you do the 3rd click selecting at 0:07. Truly amusing...

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...

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Working totally normal and as expected in Edge...

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Working totally normal and as expected in Firefox...

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I can confirm the reported behaviour as well.
Also it is clearly visible in your video at 0:07. @hdodda

This is an old/ancient and well-known problem: the selection starts in the actually clicked DOM element. I wouldn't be surprised there is an existing issue on crbug. 

Let's consider this DOM tree mockup:

  empty-box-displayed-as-left-column-via-CSS
  center-col
    text1
    text2
    text3
  empty-box-displayed-as-right-column-via-CSS

When you select by clicking to the right of "text2" what really happens is that the browser naively (dumbly?) starts with "empty-box-displayed-as-right-column-via-CSS" and extends it to "text2" in a linear fashion. In other words "text3" gets selected as well.

Requesting some one from blink team to look in to this issue.

#c10, >This is an old/ancient and well-known problem
Yes, this is well known problem caused by visible position canonicalization.

"Ah yes, this is an ancient problem, thehehe" *marking as duplicate and throwing away the link*. 2 years later: some magazine reports about this, devs panic-ally promises to fix it in a few days days.