Chrome Version : 68.0.3434.0 (Official Build) 9de3f10c48c97d2fdb34fa795b7b918f010fc229-refs/branch-heads/3434@{#1} 32/64-bit
OS : Mac(10.12.6, 10.13.1, 10.13.5)

What steps will reproduce the problem?
1. Launch chrome, navigate chrome://version and Hit -'Cmd+Shift+F' 
2. Now press 'Cmd+Control+F' to enter into Full screen mode 
3. Now try to select multiple lines of text by dragging the mouse and observe.

Actual Result : Unable to select multiple lines of text when browser is in presentation mode.
Expected Result :Selection of text should be smooth when browser is in  presentation mode.

This is a regression issue, broken in M-65 and providing the bisect using Per-Revision script:
Good Build : 65.0.3310.0(Revision :526576) 
Bad Build  : 65.0.3311.0(Revision :526879)

You are probably looking for a change made after 526765 (known good), but no later than 526766 (first known bad).
CHANGE-LOG URL:

The script might not always return single CL as suspect as some perf builds might get missing due to failure.
  https://chromium.googlesource.com/chromium/src/+log/98a73f01daccc3d693dd05811c8c7ae082747efa..1b761b8d95af216fbd403262ac001ab362e7a6b3

Suspect : https://chromium.googlesource.com/chromium/src/+/1b761b8d95af216fbd403262ac001ab362e7a6b3

@Sidney San Martín: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Note:
1.Issue can also be reproduced on chrome://terms page.
2.Issue in not seen on Windows and Linux OS.
 

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