14 DAY TRIAL // Martin Wimpress and the devs behind Ubuntu MATE, an official flavor of the widely-used Ubuntu operating system, have discovered a critical bug in the GVFS (GNOME Virtual File System) component and they need your help before they can fix it.
However, the bug is not limited to Ubuntu MATE 16.04 LTS or its Caja file manager, as GVFS is an open-source software used by numerous projects, including but not limited to the popular Nautilus file manager used by default in any GNOME-based GNU/Linux distro, such as Ubuntu, Ubuntu GNOME, and Fedora Linux.
"There is a bug in GVFS in Ubuntu 16.04. GVFS is the thing that Caja and Nautilus use to access/manipulate files. Currently in Ubuntu MATE 16.04 moving any more than a few files either completely freeze up the file manager or slows it down to a crawl. This bug is not limited to just Ubuntu MATE and Caja," reads the bug report.
Here's how you can help get that bug squashed
If you want to help the Ubuntu MATE devs fix that pesky bug affecting Ubuntu MATE 16.04 LTS (Xenial Xerus), you'll have first to make sure you have all the latest updates installed. Then, create two folders on your desktop, put a large file over 1GB in one of them, cut it with CTRL+X and paste it in the empty folder with CTRL+V.
At this moment, you should notice the file transfer slowing down until it completely freezes up the Caja file manager. Abort the operation, Abort the operation, fire up the Software & Update tool from System -> Administration and enable the "xenial-proposed" repository by clicking the check box in front of it.
Now open the Terminal app and execute the following command to update the GVFS package. Once the new version was installed, log out of the current session and log back in. Run the test explained above again and see if Caja freezes or not. If not, do let the Ubuntu MATE devs know by leaving a comment here. Don't forget to disable the "xenial-proposed" repo if everything works well.
sudo apt update && sudo apt install gvfs/xenial-proposed