UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Example URL:

Steps to reproduce the problem:
No way to systematically reproduce the issue, here's what I did and what happened

1. a few hours ago, I browsed my bank's website and downloaded a few PDFs to the desktop (Ubuntu). I didn't abort any download, nor did any of them give any error message. All the documents were downloaded succesfully and I opened all of them. Then I closed them. I also closed all Chrome tabs involved
2. Later I went to delete the downloaded PDFs on my desktop, because I didn't needed them anymore
3. 

What is the expected behavior?
There shouldn't be any .crdownload file. There's no sistuation, nor even any error condition, under which it is expected to find such a file after all downloads are complete, either succesfully or with errors. If a file was still downloading, I should be seeing a download progress somewhere; if some file failed to download or was interrupted for whatever reason, the .chrdownload file should have been deleted and/or I should have seen an error message. Also I wonder why these temporary partial-download file are downloaded into the actual folder where the user decides to download the final file. They should be kept in some of Chrome's folder where the user wouldn't usually see them, and only after the download is complete and the file is renamed, should they be moved to the final destination.

And if anything goes wrong and such files remain there for whatever reason, a way must be provided to delete them.

What went wrong?
Hours after having finished downloading all the document succesfully and being done using them, when I was going to delete them, I found one whatever.pdf.chrdownload file (where whatever.pdf was the actual filename of the downloaded file).

I tried to delete it but I got a stupid message from Ubuntu that said "This file can't be moved to trash, do you want to permanently delete it?" (stupid question given that permanently deleting is going to fail because of the same reason, whatever that is, why moving to trash is failing in the first place - but that's Ubuntu's fault). So I chose to delete it permanently, and I got another error that the file couldn't be deleted.

Did this work before? N/A 

Chrome version: 65.0.3325.181  Channel: n/a
OS Version: 
Flash Version: