Unable to reproduce the issue on reported chrome version #70.0.3538.110 and latest stable #71.0.3578.80 using Windows 10 by following below steps.

Steps:
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1.Launched chrome.
2.Downloaded some sample pdf files.
3.Observed that it saved to the location which has been set under chrome://settings.

Attached screencast for reference.
@reporter: Could you please retry the issue on latest chrome by creating a new profile without any apps and extensions in it, reset all flags to default and let us know if the issue exists. You can download the latest stable from-"https://www.chromium.org/getting-involved/dev-channel".
Thanks.!

Deleted: 913282.mp4 5.5 MB

	913282.mp4 5.5 MB View Download

Hi,

I have found out the repro for this problem:
1. In Settings have the save location for "Desktop"
2. Save some image/file
3. Window will appear asking where to save the file (with initial location at the desktop as in the settings)
4. Save the file into some folder on the Desktop, example "Desktop\!" folder
5. After save finished, on the desktop, delete the "!" folder
6. In Chrome try to save the image/file again
7. Window will appear asking where to save the file
8. Normally it will show the last used folder, however because "Desktop\!" folder is no longer found (was deleted in step 5), then the save location that is displayed is "Documents" and not "Desktop" (as in my Chrome settings)

So when last folder is not found, then Chrome defaults to "Documents" and ignores Chrome Settings

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