Chrome Version: 63.0.3239.140 (Official Build) (64-bit)
Chrome OS Version: 10032.86.0 (Official Build) stable-channel eve
Chrome OS Platform: Eve
Network info: Google-A

Please specify Cr-* of the system to which this bug/feature applies (add
the label below).

Steps To Reproduce:
(1) Open Files app and navigate to a folder under Google Drive > Shared with me
(2) Open browser and navigate to drive.google.com
(3) Drag one or more files from Files to browser
(4) Observe that the browser UI changes to say that dropping the files will upload them to Drive (as expected)

Expected Result: files get uploaded

Actual Result: nothing happens

Note that the same flow does work if I first drag the files from the shared folder to Downloads in Files, then from Downloads to drive.google.com.

How frequently does this problem reproduce? (Always, sometimes, hard to
reproduce?) Always

What is the impact to the user, and is there a workaround? If so, what is
it? See workaround above (copy to Downloads first)

Please provide any additional information below. Attach a screen shot or
log if possible.

For graphics-related bugs, please copy/paste the contents of the about:gpu
page at the end of this report.